Anarchism

I think while practice is important and more leftists should do more realistic plausible grounded things, especially when it comes to organising IRL, especially in formal unions and political parties (I'm an electoralist and believe that if populism works for the right, we must try to make it work for us), we would have no philosophy and no left at all without the kind of "fringe analysis" that OP posted. Sincere anarchist zines and niche breadtube are leftist culture and fairly successful culture too - just look at how many YouTube videos out there are "video essays" now.