I prefer looking at it this way.

Allowing for all forms of human life that don't depend on the dehumanisation of others is a basic general rule that I think is useful.

I'm not sure it's possible to escape othering in such a large world, but putting all of our energy into tending towards sharing the world, a world in common, is a good move, and I think maybe part of that means being strong enough to crush a fascist even though they're human.

But I do think that we need to trouble the whole concept of humanness in various ways also, but that goes beyond the scope of this comment! It is why I made f/Humanness though.