Lumping all reasonable adjustments and all types of work into one pile is unhelpful.
I've multiple disabilities. I have had career guidance and support specifically designed for disabled people that did entire courses on reasonable adjustments and how to discuss/fight for them.
What was repeatedly drilled into us was that what is considered reasonable is context specific and involves a cost/benefit analysis and really what we want is a work role and environment that has the least need for adjustments possible - that just works best for everyone.
So that specialist software - how much does it cost, what equipment does it involve, how will the equipment work in the workplace? I've set up accessible settings for non-disabled co-workers computers before that cost 5 minutes of time because it's just that they didn't know it was there, but if I end up - as is possible - requiring large mobility equipment, I'll have to change roles, it simply cannot fit a role that requires a higher level of mobility - which is why I applied for the role, to help keep me fit with a condition that means I become deconditioned quicker than most.
Working less time - if the workplace is very time sensitive, it's probably not a good fit, so look at workplaces where that is available to everyone, where core hours are small with a lot of flexibility. A lot of grievances on this have more to do with management not hiring enough staff to handle people - both those with and without disabilities (where I work, it's mainly child-related or just having been negotiated to 4 days, not disability related) - having significant reduced hours/days rather than at the adjustment itself.
And yes, some people - with and without disabilities - will rely on the financial and of the government and/or others. Everyone relies on the support of others in the society we've built, even if they go unseen. That is not solely an out of work issue, that is not solely a disability issue. Reasonable adjustments, while largely fought for by disabled people, isn't solely a disabled issue either and framing it as such ignores the far wider ways people get support at work - the adjustments I've made for my colleagues wasn't disability related for them, it just made them and their work more comfortable and so able to do it better. I think that needs to be the focus, not this obsession that without extra exam time people are going to go starving.
Disabled people do tend to know their own limitations.
At least for me, it's only after I hurt myself enough times.
I have it on my occupational health report not to do any manual handling without specialised training - I have absolutely hurt myself moving furniture that should already have been at least a 2 person job because I overestimate my capacity. I learned to stop doing that after I badly strained several muscles.
It's why I'm also one of a few disabled people on my team who has had to be reminded to take breaks, when I'm technically allowed extra 'self-managed microbreaks', rather than working through because hyperfocus does lead to me forgetting eating is something I need to do.