For me it’s gotta be something from ARTE (the French/German culture television channel). Either it’s the one about Chodorowskis weird Dune project or the three-part series about the history of racism. Both were extremely well-made documentaries.
Everything by Adam Curtis. It’s mostly already known facts, but arranged in a positively depressing way.
three-part series about the history of racism
That sounds interesting, but I couldn’t find it. Do you have a link, or a title?
I can reommend “Encounters at the End of the World” by Werner Herzog, it’s about researchers in Antarctica and what motivates them to be there. So many interesting people, and it gets a bit philosophical.
Fog of War (2003) is just heartstopping for anyone interested in 20th Century American history. https://www.imdb.com/title/tt0317910/
Grizzly Man (2005) is mesmerizing all the way through despite it’s quirky protagonist and predictable conclusion.