A list of social justice discussions on scientifically-oriented subreddits. Caveat: I don't agree with all comments. (academics have class privilege and other forms of privilege, so there are certain life experiences they're not familiar with, and their privilege shapes their view of the world) But I do think a scientific grounding is important.

Additionally, AskHistorians maintains a list of frequently asked questions for various topics:

Note to self: This is the search method I use to find new stories:

(this has gotten much too long though, so you'll have to delete 60% of it before it'll work)