The left instead rationalized it under "free speech is not freedom from consequences", called them Nazis, fascists, bigots, homophobes, misogynists, you'd need a thesaurus. Every slur in the thesaurus, they used. When your opponent plays dirty, actively seeks to get you fired from your job, and your figureheads get killed (Kirk) or nearly killed (Trump), why uphold the rules?
EDIT: > Admit that your position is an unprincipled one and based on feelings rather than thought.
Admit that the right has realized that neither side gives a damn about principles; but the left has no right to claim to be principled after 2020.