Leftism without the work of antiracism slides quickly into fascism.
Anarchism/socialism and fascism are all critical responses to the destructiveness of liberal capitalism. The fundamental difference is that leftist movements punch up at the brutal systems of inequality, while fascism punches down at marginalized groups to keep the same hierarchy with themselves at the (generally imaginary) top. Once leftists start punching down instead of up on racial and ethnic lines they become the ideological siblings of fascists, except they are friendly to, and are themselves, white or white-adjacent women and queers.
And please don't kid yourself that you're doing antiracist work by not saying slurs (want a medal for that?) and by saying Black lives matter. If you insist in the face of mountains of evidence that race doesn't exist as an axis of oppression apart from class, you think and act no differently than the "race doesn't matter" right-wingers. If you bristle at any suggestion that you or your friends are racist and lash out with harassment and whisper campaigns that drive BIPOC from your spaces, you are straight up being racist. If you do not look into yourself and question yourself, your friends, and how you conduct yourselves, you are not doing the work.
Those of you nice white people who whine "why can't we all get alooonggg" aren't much better. You may not join in the targeted racial harassment but you give cover to it by refusing to acknowledge the nature of it and framing it as interpersonal drama while disregarding the power disparities and systemic bigotry involved. Remember how MLK was more worried about white liberals than the KKK in his Letter from a Birmingham Jail? Yeah that's you. Congratulations.
Generalist Hometown instance with a strong focus on community standards. No TERF, no SWERF, no Nazi, no Centrist.