We all have needs.
A simple way of looking at his would be Maslows hierarchy of need.
However for you or I we can speak, and we're fairly self sufficient.
When you're autistic your brain often lacks the ability to filter out sensory stimulation to focus on certain sources. For example you're in a cafe, the lights are bright, someone's steaming milk, it's busy and there's a lot of chatter, there's a bell on the door that dings whenever someone comes or goes, there's a kid with an iPad on full blast 2 tables along.
If you wanted to speak to the person over the other side of the table you'd probably be able to do it and filter out what they're saying from this background of noise and the noise wouldn't be particularly harmful or hurt you in anyway, nor the light because the filter in your brain works to do it's job.
If that were an autistic person there's a very high chance they'd struggle. They might have delayed processing, they might hear everything at the same level, and their brain will try and filter all of this information all at once. This is overwhelming. Its like being told you've got 7 deadlines to meet within the hour at work after your colleagues have all gone home after lunch and there's a presentation first thing tomorrow kind of stress that you feel all the time in these environments. Add to this, if you can't speak, how can you advocate for your needs? You can't say " I need to go somewhere quiet. Do you have any spare sunglasses? I'm going to put on my headphones now. Let's text instead. Can we reschedule?"
Another example would be in mainstream schools.
30 kids per class, bright lights, the whole schools lunch is at the same time. Hundreds of kids in the playground all making noise and running in different directions. Nothing is predictable. The work in class isn't set out in a way you can access, everyone needs to sit still heads up pencils down, but you need to physically move to help soothe your nervous system so the information sinks in but when you move you get in trouble so you're stressed out, everybody is playing the game really well, but you're expected to play the game of life well too except you weren't given an instruction manual and when you are it's in a foreign language, on top of all the sensory input that is causing you psychological pain but you're legally expected to be there 6 hours a day 5 days a week. You need a break, you need quiet, you need to be able to move around, and you need adults there that understand this and can meet those needs.
We all need a voice whether it's a spoken voice, AAC, hand leading, pointing, gesturing, grabbing, PECS, or a very understanding and familiar adult.
I had the unfortunate displeasure of witnessing a carer take away a child's iPad for dysregulated behaviour which took away that child's voice through their AAC. The child was seeking a distraction, wasn't following an adult led task, and was therefore chastised as naughty. That child then had to rely on others to interpret his needs, which they were already doing a poor job at as they'd not noticed he needed sensory input due to dysregulation and he was using his autonomy to do that when they took it away.
We all need safety and comfort. We all need to take up space and not make ourselves smaller for the benefit of others.