The most difficult part of having autism for me is the need to analyze everything to try and figure out why people are acting the way they are.

No issues here, that attitude helps to solve misunderstandings.

I was thinking you might have autism from your post

Correct, I said so somewhere else.

They are expressing their feelings, and a neurotypical person would probably see your response as dismissive because you are telling them what they should feel instead.

I don't want to invalidate anyone's feelings, but everyone might have misdirected feelings sometimes. For instance, it is common among victims of abuse to hate themselves rather than the perpetrators of the abuse. If someone has an inherently debilitating condition, it's perfectly natural for them to hate that condition. If someone has a condition that is, for the most part, neutral, but suffers social discrimination because of it, and places the origin of their pain in their condition, rather than in the discrimination, that is similar to an ethnic minority who suffers from racism growing into hating the fact that they're an ethnic minority. If someone literally says "most of the struggles I have with the tism come from trying to live in a world designed by NTs", that pretty much sounds like they do fit what I'm saying. Because autism is a wide spectrum, I'm aware that some people in it do actually have innate difficulties due to being on the spectrum that wouldn't have emerged in a perfect environment, and if you read my original comment, you'll see that I'm speaking in terms of possibilities and conditionals. But there is also a lot of autistic people who shouldn't unload their loathing into being autistic, but into the fact that suffering discrimination through their whole lives has made them accrue so much trauma that they've developed a different debilitating condition.

I am thinking that you might be getting downvoted because the problem seems to be an emotional subtext that isn’t immediately obvious.

That's the case for at least some of the downvotes. There is also at least one user who was defending the narrative that every person on the spectrum should hate the condition.

I am thinking they expect you to identify yourself as having autism, and without that frame of reference a neurotypical person might jump to conclusions that you aren’t?

Do you mean this in the sense that I didn't initially mention I'm autistic, or in the sense of the dichotomy "being autistic vs having autism"? If it's the former, that's on their part for jumping into conclusions. If it's the latter, they should read into it and accept the reasons that lead some people to prefer one kind of language over the other.

I appreciate your interest into having a clear understanding of the discussion. Have a good day.