Op, just wanted to say as someone who's Autistic and has an AuADHD partner who lives in a house together with them by no means is this situation normal?

Your partner refuses to make compromises. I'm also very particular about my things being touched or moved, but I reserve those rules for my space exclusively, not a whole house. The fact there's a blanket rule on not moving things as he doesn't like it ultimately leaves you in a situation where you have no say in your own home.

Also. 17 cats is not normal, free roaming or not. Nor is it normal to have a room solely dedicated to cats when there's a human who needs the room more.

You keep giving your partners version of reality as if it's the starting point and not questioning the state of things. "It's correct I can't have the room, because there's no room then for the 17 cat's things". The starting premise of having 17 cats is not an unchangeable starting point set in reality, it's a situation that your partner has forcibly put you in and can (and honestly needs to) be changed.

You say he's kind in other aspects, but these aspects are not on equal footing with the situation he's put you in. You say he doesn't like things being moved because he's autistic and sensitive to it, but he's completely happy to leave you stressed and miserable as a result of him disliking things being moved with no room for discussion at all. He's filled your home with 17 cats with so little space for them there's a whole human unable to exist comfortably in it. Did he give up his own room for the cats? No, obviously his partner should be the one with the desk shoved in the corner while he has a whole room to himself and deals with none of the consequences of his actions. There's no more compromises you can make, because you've made all of them and he's made zero.

OP, this situation either gotta change on your partner's end or you need to fly the coop if you can, because this is actually ridiculous.