> The first time a black coworker gave a black thumbs-up reaction on slack, I noticed I didn't want to +1 it. I didn't identify with it, it didn't feel like it was coming from me.

Why wouldn’t you identify with a +1 from a black (or other race/ethnicity) colleague?

The question is a bit aggressive, but if possible don’t consider it like that — I live in an (unfortunately rather conservative) part of the EU and TBH I’m often surprised with the race/diversity activism. I usually support them, if nothing else then because I’m clearly ignorant and not affected by the challenges some of my coworkers have to put on with.