Are you implying that people in favor of and/or implementing affirmative action members share some culpability in far-right terrorist acts? Huh. In my book, deciding to leave civil society for untargeted violence against innocent people of some other group immediately puts all the responsibility for your actions into your lap. You don't get to say it was because of some vague ideological pressure at that point.
I'm not arguing who's responsibility it is. I'm just pointing out that in practice, when you force an ideology on people + take away any outlet for them to express dissent(through deplatforming/censorship etc) then this is the kind of thing that ends up happening. That being said, whenever someone enacts a policy that affects others it is important that they consider the effects of externalities. While they may not be directly responsible for those externalities, it's irresponsible not to take them into consideration. Pointing fingers after the fact doesn't bring people back to life.