There was a post on !mildlyinfuriating@lemmy.world called "Lemmy is losing the war against reddit. How do we change things?" Looks like it was removed but there were a couple good discussions there. In a discussion with (I think it was) @hendrik@palaver.p3x.de we came up with this.
Leftism is strange because most people aren't left-leaning in every topic, just ask them about veganism e.g. Suddenly, a lot of people sound just like your average right-winger. Unfortunately, these people suck at acknowledging their own biases - just like pretty much every other human. They only support necessary social change up to the point they too would have to change.
The really strange thing is, call them out, and they may even turn right entirely, just for calling them out. I remember reading lots of people saying this after the election, despite the right having as much infighting as they have inbreeding. But it works for them.
The point is, I think a lot of people like to think about themselves as being on the left. They acknowledge it to be the correct way and want to think of themselves as being a good person - but they really aren't, and it often shows.
And I repeat, that's okay. We all suck at this. But we should still strife for better.
There's always a bit of "no-true-leftist" dynamic within left-leaning circles. Vegans have gotten upset at each other for stuff like feeding their pets a diet with or without meat, boiling over into Fediverse drama (not trying to open that discussion here but just highlighting that it has been hotly debated). If we let small differences get in the way of big progress, of course conservatives will win and take us backwards because they will use any opportunity they get, and are somehow better at setting aside differences on unrelated issues than leftists. I don't have much of a solution besides putting my focus and attention on issues that are more important to me, such as the class war over culture war stuff.
Call me a lib, but I occasionally agree with things conservatives say even if a lot more times I disagree. That doesn't make me a conservative but there are some that act as if I was.