Status jockying. The mob always needs a target, otherwise it loses momentum. But it's hard to get riled up about your actual enemies, because they're far away, unreceptive, or don't pose an immediate threat to your social status (e.g. patriarchal Islam). All the conservatards have been purged from your life, so you don't actually have to deal with them most of the time. But the mob still needs a target, because it's what binds the group together and provides that exhilarating feeling of being part of something.

You don't want to become the next target, so the most proactive thing to do is try and paint a target on someone else. So you need to show your social justice bonifides, you need to irrevocably demonstrate how superdupersocjus you really are. What better way, after all, to flush out enemy agents--the pretenders and hyopcrites--who are hiding within the politically correct fold, than to keep raising the cost of membership by ratcheting up the absurdities to ever greater heights?

The absurd beliefs are like the peacock's tail--useless and ridiculous, but a conspicuous and hard to fake signal. In this case, what’s being signaled is ideological allegiance rather than virility, but the principle is the same.

The movement becomes an end in itself, for it must keep moving or it will die. It doesn't even matter which direction its moving, or even if it comes full circle. So saying 'There is only one race, the human race' is now a microaggression, and racism somehow becomes the cause of, and the solution to, all life's problems, and intersectional feminism is apparently now the grand unifying theory of everything.

They eat their own because the revolution must never end, even if it just keeps revolving on the same axis. Moloch wins.