Banning vs. not banning are not hallmarks of leftism, rather it's the difference between communities that are making an effort to be inclusive (a hallmark of leftism, btw) versus communities where the mods are so tired and overworked that it's easier to ban people than adapt to the disruptions they may cause (a capitalist reflex that prioritizes being palatable to everyone over being fair to everyone because it's more time-efficient to be blandly palatable and to enforce case-by-case fairness).

So yeah, from a certain point of view, because of the simple fact that you are being tolerated marks Lemmy as a more leftist platform.