My feeling is that there only two kinds of people who would find this argument persuasive: (1) people who already strongly believe it, and (2) people who don't read it carefully. The argument relies on its audience assuming that any noxious behavior involving race is "racism", and that simply isn't the case. There is no equivalence to be drawn between Paul Gosar denying the Holocaust and overeducated, cliquish busybodies at nonprofits "co-opting" minority identities.

The minorities can speak for themselves on this issue (and are, by voting out the co-opters and switching parties). At least, they can as long as Paul Gosar doesn't have his say.

I didn't say that the Republican party was going to lose all minority support, or that every Republican is racist. As I said, I don't think it's productive to describe any party as "racist" (though apparently you disagree). But if I asked you to guess which party has the big-state governor candidate who paid $5000 to be featured prominently on the openly white-supremacist site that featured the Tree of Life shooter, you would not honestly have to think carefully about the question. It is, as I said, not a mystery why people say that the GOP is a racist party; it is many things, and one of them is the party for racists.