Antifa will be equally indefensible after they gas 8 million people.
Antifa beats up old people, destroys property for no goddamn reason, and hurt people with bats and bike locks. The Neo-nazis say racist shit that is largely false and they antagonize a lot of people. They both sound idiotic and act like a group of fools, can't we just say they both suck and move on to actual policy questions....
https://en.wikipedia.org/wiki/Antifaschistische_Aktion
So they are affiliated with groups that killed millions, just as neo-nazis are ideologically related to the original version.