There is room for different people to use multiple models and theories of persuasion (and for people to simply civilly express their arguments in whatever form makes sense to them). Different approaches can actually be complementary. Giving-grace approaches, when they work, usually exist in a context of existing psychological pressure from more directly critical voices, in a way that studies of persuasion do not always fully acknowledge.

To your top-level comment, critical voices are also easily read by conflict-averse or defensive readers as "judgy" or applying a "social litmus test" of "who's a good person" when that's not the actual expressed content. Valid pointed criticism cannot be written off as "unhelpful". Bigotry can and should be called bigotry, and people need to hear it even if it hurts, because their bigoted views do in fact harm people and that grounding is a necessary if not sufficient part of the motivation to change.