The most infuriating answer I see is the one that places blame on identity politics and the divisiveness that comes about as a result of disagreement of tactics and the like. There's this Kumbaya "why can't we just get along" hand-wringing nonsense. So I've been having some severe disagreements with classmates. But after that we can get along just fine.
Here's my metaphor: we live in different houses. Each house has its own rules and household culture. Maybe I like my house neat and you don't mind sloppiness. This doesn't mean we have to fight over our respective ways of handling our houses. It's perfectly okay for us to live in our own houses. We shouldn't be fighting over this, because there're people who are trying to tear down our houses. And when we argue about how to handle our own houses, we're just making their job easier.
The thing is that we're dealing with people who aren't just living in bigger houses, but can hire people to take care of those houses while they're busy sabotaging our houses. They live in gated communities which are safer because they have the means to do so.
So, it's perfectly fine to critique one another's style of running our houses because maybe the dialog will be useful. But we need to learn how to trust each other in running our own houses, and work together in preventing our houses from being torn down. We don't need to be living under the same roof to get stuff done together. We're not all the same. Stop yelling at me about how it's not important for me to spend my time cleaning my house and there are better things I could be doing.
This metaphor is a work in progress.