I know maybe half a dozen signatories of this letter, although none of them particularly well. I also know a number of people who didn't sign this letter, in some cases to my surprise.
My opinion of the "Jeopardy community", which one gains entry to by having won on Jeopardy, is not high at all. Demographically these are exactly the sort of people whom one would expect to be wokescolds, and they have additional reinforcement from the self-confidence they've gained by having won on Jeopardy.
If I were to venture an explanation, I would say that these are people who are anxious about their whiteness, and the only way to alleviate that anxiety is through "anti-racist" action. The point here is not actually to alleviate any social ill; the action is the end in itself. That's why the ADL is the villain to these people; in denying that their action is anti-racist, they are denying these Jeopardy contestants the right to self-actualization.
I learned of this petition at the time it was happening; it was ludicrous even at the time, since anyone could see (and plenty of people had seen) that the contestant in question was counting off his victories on his fingers in previous episodes. These people knew this full well when they chose to sign their names. I feel bad for the man in question that he's had to be subjected to this, but on the other hand this means that he's not part of the Jeopardy community, which is a net positive on the whole. I am surprised this story would make national media, but I guess it really does have everything.
I've made it to tryouts twice, but haven't figured out how to get them to pick me. Had I been on the show, especially had I been a champion, I would very vocally come to this guy's defense and chastised everyone dragging him through the mud, while also reminding everyone that I'm a liberal democrat myself.
