The goal of popper was to create asymmetry, where Marxists are allowed to call speech of opponents violence with no reasoned argument and with that justify real violence by Marxists. Stopping volk-Marxism, nazism, is not where this ends.

As always it ends it gulags filled with academics, Trotskyites, any competing faith (Christianity, Islam etc), anyone that has a rich person somewhere in the family tree, whomever annoyed the commissar etc