But that sidesteps the question of what responsibility they have as a company whose profits are, at minimum, powered by that problem, if not exacerbating the problem.
“Privatize the profits, socialize the costs” is not sustainable.
I don't think it's established that that's the minimum. Facebook usually argues that it's a small minority of their content and I don't see any evidence against that (it just gets a lot of scrutiny). It seems like if you magically removed all the "bad actors" they'd make just as much money.
The church (as well as the integrated state) has been doing it for thousands of years. I think treating the general population as a somewhat renewable resource to be mined/harvested has a longstanding tradition and history of being one of the most sustainable things in human history.
Depending on how tax money is spent (i.e. in ways that benefit a subset of society, rather than all taxpayers) this is perhaps the most common and longstanding tradition we human beings have.