Any weak male regardless of race or color.

From personal experience I'd have to say threatened male identity. Once they finish beating on and subduing their loved ones, then they can bring the rest of the world into line.

I don't pretend to know. The so-called "incels" movement does not seem to have an overt racial element to it, I would presume that a latino or asian or black man could at least in theory consider themselves "involuntarily celibate". But I would be unsurprised to find that the incel movement is primarily white ... let's see ... yeah, sure enough: "Self-identified incels are mostly white, male, and heterosexual." per [en.wikipedia.org] with three citations provided.

So maybe ultimately it all comes back to the loss of WASP hegemony, at least here in 'Murica. Subgroups that don't have an explicit racial complaint or dynamic, like the incels, still are displaying white privilege in another context.