Racism is just less legally dangerous. There would be people posting snuff or CSAM videos, would that “sell”. Make social networks tough on racism and it’ll be sexism next day. Or extremist politics. Or animal abuse. Or, really, anything, as long as people strongly react to it.
But, yeah, to avoid any misunderstanding - I didn’t mean to say racism isn’t an issue. It is racist, it’s bad, I don’t argue any otherwise. All I want to stress is that it’s not the real issue here, merely a particular manifestation.