(IMO) Among other things, confrontation & hostility. In recent years, there has been a backlash of radicalism regarding being overweight/obese, with clarion calls like, "Why fat doesn't mean unhealthy", "Just because you're overweight doesn't mean you're not healthy", "You can be fat and fit", etc. etc.

While there is some truth that weight isn't everything, and people should not be discriminated against/ostracized for legitimate weight issues, some—perhaps many—are using this as justification/rationalization for being unhealthily overweight. Some are just defensive; others are downright aggressive/militant about it.

See also my previous.

Doc