The problem is that a lot of people, specially Americans, have interiorized "red scare" propaganda notions, even when they see themselves as Lefties.

If you don't just mentally go "uuh, commies" at the mere wiff of communal solutions it's a lot easier to actually look at certain ideas and judge them on their actual pros and cons, as is spotting authoritarianism for what it is (whether it claims to want to implement leftwing notions or rightwing ones) and tribalism (of the kind that supports Fascism whilst claiming to be leftwing, and I include both Putin supporting "communists" and Zionism supporting "liberals")