It's inflammatory, outright disinformation, outright misinformation, or just something the service owner doesn't want to carry. Discussion a lab leak hypothesis is not the same as claiming COVID leaked from a bioweapon laboratory or was intentionally leaked for <reasons>.
That being said, social media sites flagging posts is very different from outright censorship. It's not uncommon for someone to actually get censored/removed from a site claiming its censorship over discussing some topic when really it was a history of dipshit behavior and flagrant TOS violations.
so, the vast majority of social media then? what makes this issue so special? why did all of the major social media networks censor/"flag" anyone publicly speculating only certain speculations about this issue?