I am autistic with ADHD. I wasn't diagnosed until I was 37. To the person who said we wouldn't be diagnosed unless we were showing communication challenges or repetitive patterns, I am afraid that isn't true, I didn't show either.
To the person asking their child to make eye contact with the lollipop lady, please be aware forcing your autistic children into uncomfortable behaviours can cause masking which is really not a good idea. Just because society and your expectations say they should make eye contact doesn't mean it is the right thing to do for them, that is a very ableist way of looking at the world and is like behavioural therapy which is really disliked by the autistic community. Just because neurotypical people don't think brushing hair can be painful doesn't mean it isn't for your child.
I was diagnosed late on, I have an autistic child who is growing up where we are very open about who we are. Our explanation has been that different people have different brains just like people have different coloured hair. His brain doesn't like loud noises or sticky things but is amazing at climbing and working things out, my brain means sometimes I need time to myself because there are too many noises and I need my brain to calm down.
I have had a job all my life, I have a very successful career, I am social, my networking skills are very good, I am over empathic to a point where I get upset and sad at ridiculous things on tv.
Autistic people mostly don't like using functioning labels such as lower/higher and the now not diagnosed Asperger's. This is because it takes away from the incredibly different ways we experience the world and face challenges in it. Someone could be non-verbal, have low motor function yet hold 3 phds and run rings round most of us mentally, yet society would call them low functioning and treat them as such because they don't see past the outward appearance. Simultaneously no one sees the challenges I face, I would be considered high functioning in old terminology yet I face daily challenges. We are all disabled purely because the word disabled means that the world around us is not designed or adapted for us.
I do this advocacy and work as part of my day job. There are so many things for people to learn about neurodiversity and being neurodivergent. First stop should always be the adult voices, ask questions, hear what they are saying, they are your child grown up. Yes some of us may not be as diplomatic as you would like, yes we make you uncomfortable or tell you what you are doing is wrong, we do it to help teach, to make sure those without a voice or who can't explain yet are heard.