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.

I think Lemmy is just more open than reddit rather than more left or more right. People are actually discussing different viewpoints with the intentions to find compromises that work, and haven't yet fallen into the trap of becoming entrenched and just fighting over which team is right... mostly, seeing some tribalism on here but you can't have a group of humans communicating without it showing up.