It’s not so much fat acceptance but rather just accepting people who happen to be fat as valid human beings instead of seeing them as less than perfect. Because they are valid people. Sure we need to promote healthy living as well but we don’t have to look down on people who do anything less than looking like a MCU character on steroids.

The idea is supposed to be “don’t be a shithead to fat people, acting like an asshole to them doesn’t help them lose weight and gain self-confidence” but for some reason that morphed into a kind of “If you say anything negative about a fat person ever, you’ll be accused of being the worst person ever.” Though at the same time, this is mainly just one of those conservatives worrying way, way too much about a tiny group of people who no one would’ve ever heard about had they not gotten so mad at them existing.

It’s some of what other commenters have said, but also, a lot of the “science” about the dangers of being fat are based on extremely shonky statistics. While it’s probably true that being extremely fat is quite bad, the evidence for being a bit overweight being bad is actually extremely weak. BMI in particular is completely made up nonsense. Combine that with the fact that doctors won’t take real health complaints seriously when they think people are overweight, and that fat people are paid less for the same work, etc, and you end up with another very effective method of class oppression - rich people can get lipo, steroids and ozempic and poor people are looked down on for being fat like it’s their fault even though the fact that it’s the majority of people shows it’s something wrong with the whole societal food supply, transport infrastructure, etc.

I’m old enough to remember when shitting on fat people for literally no reason was not only common but the butt of a bunch of jokes. Reddit even had a community where people took sneak pics of fat people going about their business just to say the most vile things to them for having the audacity to leave their homes.

I feel a lot of the early body positivity/anti-fat shaming movement was a response to this sort of online discourse that helps no one and just spreads hate. Them it evolved into this “I’m fat and healthy” thing we have nowadays, that itself does a lot of harm.

There’s being an asshole and bullying and shaming people for sadistic pleasure or out of some fascist idea of them being inferior and then there’s not upholding any standards or aspirations of human health and instantly incinerating anyone who suggests people should be healthy, shouldn’t eat half a package of oreos every night, should exercise, that most people with a good diet and exercise that results in a healthy BMI will have a happier life, a higher quality of life, a longer life, etc. There are some amount of people obviously who have some conditions that make this more of a challenge. But encouraging that aforementioned healthy lifestyle while offering some understanding (but not justification) for stressors under capitalism leading to unhealthy bodies, weights, habits, etc is the right course of action.

A comradely hand up and encouragement not a derisive laugh and a shove to the ground basically is my feelings on it.