Don't worry, the rest of us don't like the process either.

One of the best things you can do to prep is to find someone you can relate to at least a little bit who's already been through it, ideally someone with a few years under their belt, and do mock interviews with them. Interviewing sucks, it's not an easy skill and you hopefully won't need it very much. The first ones are always the hardest.

"None of this has anything to do with your ability to perform the desired task" is the major flaw in this. Social interaction is a pretty huge part of any job where you work with people, and so-called "chemistry matches" are often rated as the top thing teams are looking for. This is why so many hiring managers will bring in other team members into interviews.

Edit: just because you don't like this fact doesn't make it less true. People want to work with other people that they don't want to strangle.

You just have to figure out the ways your autism makes you a good worker and explain it to them. Honestly chatgpt could probably help with the wording if you just explain your autism to it lol