Not all backlashes go too far. However, successful social movements almost always go too far and thus provoke legitimate backlashes.
I have no idea what you would securely base that on. It seems to me (correct me if I am misinterpreting you) as if you are essentially choosing to say that one sort of thing (effort/protest) is generally more problematical than the other (resistance/backlash). This is what constantly baffles me about you. The obviously reasonable and accurate way to say it is that both the efforts/protests can go too far (or have a 'wing' that goes too far) and the resistance/backlash can go too far (or have a 'wing' that goes too far), and not broadly distinguish between the two, because I really, really think, in fact I'd bet money on it, that neither you nor anyone has the objective or conclusive data or evidence to show that one sort of activity is worse or more problematic than the other, all things considered.