While I agree with the gist what you’re saying, it’s perhaps just as important to make sure that you’re hitting the target when you pull out the big guns and to minimize collateral damage. We ought to be careful to distinguish between the actual Nazis, racists, and white supremacists from the greater majority of people who unwittingly support/enable racists (or just happen to have been born white, or lean conservative, etc.) instead of indiscriminately painting everyone with the same broad strokes.
First, it’s a matter of basic decency. But perhaps more importantly, it’s strategically unwise and counter-productive to keep missing the mark because after a while it becomes background noise that is increasingly easy for your opponents to ignore since they can dismiss it as just another buzzword or rhetorical tool in the liberal toolbox that they’ve heard so many times before in every dialogue and context they encounter. But, of course, it shouldn’t be merely these things. It should either immediately shut someone up or force them to back-peddle and apologize. I fear that these words are losing the efficacy that they once had due to their overzealous and imprecise usage.
If someone were to ask “How was I/that racist?” a common sentiment is that if we have to explain what racism is then that person isn’t going to get it anyway since they’re the very definition of the problem rather than the solution. But this is a cop-out, and I get the impression that some of the self-styled anti-racists could use a refresher as much as those that they condemn, since I see a lot of conflation and imprecision in their rhetoric, which doesn’t evince their understanding but just muddies the waters of the discussion.