Worse, it could be self-reinforcing. Let's suppose enough people make a claim that AOC is an extremist, and she gets removed. Then people who agree with her get claimed to be extremists. Unless the algorithm is very careful, it might remove them as extremists because they share ideas with a known extremist. Eventually all the Democrats get removed because they share both ideas and an organization with extremists. And then the neutrals and moderate Republicans get removed, because they share some ideas with known extremists.
And Facebook winds up with only 10% of its users surviving the purge. And so they wind up with only 10% of their revenue surviving the purge.