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.