A claim of “popular” is not a claim of “mode” - a claim of “most popular” would be (although not enough to distinguish unimodal from multimodal), I left it vague because more precise quantification is irrelevant to the point.
I’ve been enough of a “US white left-of-center liberal” myself to judge that I don’t need studies to know which beliefs are popular among “my people”. I hear them every day, echoing - and echoed by - our echo-chamber “news & opinion” sources
Can’t say I’ve paid it much attention in recent years. Last time I did, “all races can be prejudiced, but only whites can be racist” was the Correct View™. Like here:
https://www.aclrc.com/myth-of-reverse-racism
While it still largely makes good sense to me, I don’t want to see the PSF insisting than any other view can only be held in “bad faith”. Other views are common too. Among people of my age, very common. I can attest from personal experience that some people near my age never even heard of the view the PSF endorses.
It’s too simplistic for the global world anyway. For an extreme example, there are a total of thousands of castes, races, ethnicities, and religions that might claim group-based discrimination in India, but relatively few “whites” left in sight.
Do all the power dynamics analysis you like, but nobody is going to build a multi-million entry NxN matrix recording which pairs of those are necessarily “bad faith:” claims. Well, sure, @kknechtel might, but he wants to get back to packaging 
.