Autism is a much broader category than it used to be.
There's actually some evidence now that ADHD and Autism are on the SAME SPECTRUM, they're just different manifestations of slightly different brain wiring. For some people, it's more of an impediment, but fundamentally, the impediment is that we don't allow those people to be themselves. They might stim by flapping their hands a bit or moving around (I have ADHD, and I ALWAYS have to have something in my hands during meetings; I also 'pain stim', where I might press the tip of a paperclip against my finger. It doesn't HURT hurt and I don't break the skin, but the stimulation is something that I do basically unconciously).
Anyway, when we talk about neurodivergence, some people need little to no accommodation and some people need lots. I actually don't think having tight time limits on tests makes any sense. In my work, I get lots of time to research and figure out answers, and if I do it enough, the answers become easier to come up with. Are we trying to test whether people know things, or whether they deal with time pressure the way we think is necessary (again, for no good reason).
You gotta pay people to monitor the exams anyway, just let people have the time they need. If they get 100%, great, they know their stuff. What's the issue?