Comment by csande17

The only explanation I can think of is that GP is, somewhat tautologically, defining contrast as "the value returned by WCAG 2's formula for computing contrast" (and, probably, assuming that WCAG 2's "science" has more basis in reality than it actually does).

I can't speak to Material You, but I've seen this sort of thinking at companies that are more concerned with legal compliance with the strict wording of WCAG 2, rather than on-the-ground user experience. People can even learn to ignore their lying eyes and fairly accurately guess what the WCAG 2 "contrast" metric for a given pair of colors will be, independently of how easy or hard the colors are to distinguish from one another.

Hopefully WCAG 3 will incorporate better color guidance from places like APCA, and at the very least these companies will stop producing unreadable black-foreground buttons and badges all the time.