If someone (say centre in politics, so not completely right wing) is blind to their racism, say that they just can't understand why their behaviour is racist, calling them out on it won't help them in the long term. They're going to get on the defensive and likely have on social media alt rights who defend them. So there's a likelihood they start associating with alt right people more and more, because that group is willing to accept them.
If you knowingly vote for a racist because you were called racist (BUT TOTALLY NEVER WERE RACIST, EVER!!!!!), then chances are that you were racist all along, actively so, that the reason you were called earlier racist is because you were racist, and that you would have voted trump anyway.
Trumpers don't vote trump because they got called racist, it's because non-white people have rights.
To be honest, I view it as rather telling that we have to change words to appease white people before changing actual action that gets actual non-white people killed. The discussion is here is literally about protecting white fragility over non-white lives. White people's ego, the wish to feel that one is an awesome person, apparently matters more than lives, even when we objectively know that there is a problem and that it kills non-white people.
I mean, we've got white people here that are super annoyed at such discussion that doesn't specifically reassure them it totally doesn't mean them, and think that everyone else is racist towards them if the wording isn't super specific about only meaning ~some white people~. And yet the same posters were often seen saying blatantly racist stuff. It's completely bonkers. No other group is that fragile, none.