AllenKnight

Other people have articulated very well. I think there are different parts of the "fat movement" that get balled up into the acceptance piece.
I like that there are more bigger bodies out there doing "regular things" like yoga, cooking, running, kayaking, dancing, living... and it's not as shocking as it may have been years before. I think that's important, especially for those people whose body is happier at a larger weight. Not everyone wants surgery or wants to starve themselves to a calorie deficit to be "thinner" when they feel good at the weight they are at. And some of them are at 200+ pounds. I think that's important to recognize.
I'm not sure any human, unless super tall can be truly "healthy" at 400 pounds, though. But they shouldn't be barred or shunned from life because they are that weight. But, they should not be lied to by a doctor. I'll be honest, though, sometimes I question the amount of medical complications blamed on obesity as a whole just because it's easier to assign blame to.
I've been relatively healthy as a bigger girl (especially when I was younger). I'm still able to do cartwheels at almost 50 and close to 300 pounds. I can understand how some people are happy with more padding - or don't care. But my weight is catching up to me, and I want more freedom in my own body.

This is an RA get involved moment. Get the building supervisor or other higher Student Life folks to step in to help you help your picked upon roommate. Covid screwed up a ton of young people’s lives and everyone is a bit raw and new. I’m very concerned about your “fat” roommate and his possible depression and or thoughts (suicidal). Other than calling in help from trained older school staff (please do ASAP) you can stand up for him by just telling the others “that’s enough.” Interrupt the teasing. Your kind roommate needs to know he’s got an ally!