AIBU to struggle with having to hide my genuine opinions about colleagues at work?

How do you distinguish between being authentic and being unnecessarily blunt?

You don’t. I can’t stand the type of people who say things like ‘I speak my mind’. Learn to hold your tongue and don’t be rude to people.

With the desk comment, why do you think she is saying it?
Sometimes comments like that can be subtle bullying, other times they can be just a genuine thing. Maybe the person has a form of OCD and struggles with messy desks for example.
If you think its meant as a put down, Id say something like 'you seem to be very focussed on my desk, do you need some extra tasks to do?'
If she genuinely is a germaphobe or similar Id probably make an effort to tidy the desk a bit on the other hand.

This as nothing ti do with autism and everything to do with you being rude. Please do not use being in the spectrum as an excuse ti not understand general politeness. You are in employment so its safe to assume you are quite capable of this as it sounds like you work in an office.

When she comments on your messy desk, just say ‘I like it like this’. That’s not hard and doesn’t invite drama of any sort. To your wider point, everyone NT or ND, has to adopt a work persona (or mask, if you like) and hide their true feelings about annoying colleagues.

This. It's part of your job to behave in a socially acceptable way to your colleagues, I'm afraid. There are some jobs where this is less important or onerous than others.

Noise cancelling headphones are god's gift to the office in my view. No better way to cold shoulder people you can't go beyond "civil" with.

Despite what you might read on LinkedIn, it is absolutely not necessary to bring your authentic self to work.
Autistic or not, part of life is having to rub along next to people that you don’t like. I doubt there are many people who find this easy all the time.
It’s work, you just have to deal with it and get on with your job. No need to be best friends with your colleagues, and no need to be rude either.

Edit to add: stop using neurodiversity as an excuse for being poor at professional relationships. Do you really think that all neurotypical people are always being their authentic selves? Of course we are not! As if I want to hear about half the stuff I have to listen to in my professional and personal life, but that’s just what you have to do sometimes, unless you don’t mind people thinking that you’re an AH.

It's not politeness, it's being a professional!

yup. That is what it is like for everybody.
I would also say that working with people you dislike is what good manners are for.

I “listen” a lot and just make noncommittal noises as “engagement”.
Then I just keep it professional, polite and helpful.
I focus A LOT on the work and find extra stuff to do if needed . Since I work in a school, that’s pretty easy. There’s always extra stuff to do.

It works 99% of the time. When it doesn’t, it gets ignored as I’m normally so professional, polite and helpful, so I must just be having a bad day. It is exhausting though.

Totally agree. We are ' masking' our real selves much of the time.

You don’t have to give your genuine opinion on anything. You simply don’t have to.

I have 3 coworkers who I deeply, deeply dislike. I keep every interaction work focused, mind my own business and don’t give them any opening. That’s it. It works and I’ve never been involved in any workplace drama with them.

1. How do you work alongside people you genuinely dislike without feeling you're constantly pretending? - if you dislike them as in despise them and everything they stand for, and also have to actively collaborate with them regularly, it's incredibly difficult. If you simply are not that keen on them or don't have much in common, and are working alongside rather than with them, it's a lot easier. It comes down to being polite but minimalistic in interactions. I don't see politeness as pretending because I believe that everyone is entitled to basic politeness unless they are behaving appallingly. If you are actively faking a big interest in their interests and pretending to take pleasure in their company when you don't then you are pretending and are obviously going to feel like you're pretending.

2. Is it acceptable to be polite but emotionally distant, rather than friendly? - yes, unless you work somewhere where networking is crucial to success. As a bad faker, I would not do well in this sort of job. I would argue that we don't need most people to be our friends at work or in life generally and it's generally a waste of energy to fake interests we don't have unless we have a very specific rationale for doing so. For one thing, it's cruel as if the other person falls for it, they're getting encouraged to go on about stuff we find boring and that is sort of mean in a way.

3. How do you set boundaries with colleagues who irritate you without creating conflict? - you are polite but direct. 'I would really like it if you would do x / stop doing y.' Add a concise reason if you want to. With the work space for example I would simply state that I like to have lots of things out at once and it suits my style of working. If they violate your boundaries / ignore them, you can draw attention to what you previously requested. The trouble is that setting a boundary even politely can be read as rude by some people and might lead them to like you less (naturally people tend to like being able to walk over others or not filter themselves, and boundaries can make people feel self/-conscioys, defensive, embarrassed, irritated etc). So it all depends on whether this is worth the risk to you.

4. How do other autistic people cope with the expectation to filter their genuine opinions at work? - am not autistic so can't answer this one but I asked my autistic sibling who says that being polite is just part of getting by for everyone and he chooses jobs where interaction with others isn't continuously necessary so that he can have a break.

5. How do you distinguish between being authentic and being unnecessarily blunt? - to me authenticity is about what we think and feel and believe, and acting in a way that fits with that as much as possible. We all probably have bits of ourselves that conflict, eg the preference 'I don't like materialistic people' might motivate you to want to be rude to someone but rudeness could conflict with the value 'Don't treat people like dirt'. No one gets to be fully authentic and unfiltered in how we express ourselves if we want to get on in the world and with others. On the other hand, I do think that firm, honest directness can be mistaken for overly blunt rudeness, especially when it comes from a woman or a member of certain racialised minority groups, and that this is really unfair. Which one people think it is will depend on context. It can be especially hard to start setting boundaries when people aren't used to it because they are likely to be surprised.

Firstly I'd suggest you get rid of the notion that being 'your authentic self' at all times is either necessary or desirable. At work it's your professional self that's required and sometimes that does mean adopting or concealing behaviour that feels 'authentic', because its not utilitarian in that environment.
Do you imagine that everyone sitting in the meeting with the boss is really enthusiastic about the project? That no one is bored to tears or who would rather it was shelved simply because they don't want to be bothered to do the work? Yet no one says so. They sit up with their listening face on, and nod along, only speaking up politely if they really have an issue.
Dealing with colleagues you don't like is exactly the same.

We all feel like this OP - autistic or not! We do not choose our colleagues and we may or may not like them, but we all have to bite our tongues and get on with our jobs. It's called being professional.

I blame the 'take your whole self to work' nonsense that's been talked about in recent years. IMO, no one should take their whole self to work! You should take a curated, professional version of yourself and leave your personal opinions, baggage, politics, likes and dislikes at the door. If you have colleagues that you genuinely like, then great, but these are a random bunch of people who you just have to make the best of. If this woman is making you feel uncomfortable though by complaining about the state of your desk, which is none of her business, I would speak to my line manager and see if someone could have a word with her about keeping her opinions to herself.

Conversely, it wouldn't affect me at all - unless it was spilling over onto mine.

We are all NPCs (non playable characters) in everyone else's life.

A lot of the time people are not thinking anything about us at all.

Work often forces people into conflict eg: Sales can't ship stuff because Finance have put accounts on stop etc.

Dealing with other people smoothly is a skill everyone has to learn over their working lives.

Fortunately I've always worked in places too busy actually getting stuff done to bother with "bring your authentic self to work" do gooding HR stuff, or whatever it was originally supposed to imply.

I'd probably try to find at least some redeeming features within them. If that was impossible I'd just be polite but not really hold any meaningful convo. If they were making me upset or bullying me then I'd tell their manager.

It would bother me if colleagues had very messy desks. If it's messy enough to comment upon, it's not a professional workspace.

Its so wearing.....I ended up getting a job where it didn't matter if I was rude (in a funny way) as it was taken as banter. I fricking love my job now!!!!!!!!

I don't feel that strongly about colleagues. Some I really like, others I'm indifferent to. It's rare I find anyone objectionable.

No one expects you to be best friends with your colleagues but you're being pretty judgmental about the one you talk about. So what if she likes handbags? Why does that provoke such a reaction in you?

Yes, it's a bit like 'I speak as a I find'.

AKA rude.

I've never come across anyone who says that they are being their "authentic self" to be anything other than judgemental and rude - but very thin skinned so if someone says anything back they are traumatised.

@YourWaryPlumBalonz
I had exactly the same problem! She would come and sit at my desk talking about hair extensions and Why Was Diana Killed by the Royal Family. All things I don't give a shiny shit about. When the office manger was there it wasn't too bad, but as soon as she was out - anything went. I HATED working with her, I had no interest in her or her family etc I ended up leaving as I couldn't stand it any longer.

There are people I don’t like at work and there are people who don’t like me . All I ask is that people are as civil and polite to me as I am to them. It’s a place of work not a social club . I also know that once I leave I will be forgotten about so don’t overshare or socialise outside of work . It’s easier just to be polite and avoid people I don’t like as much as possible.