Haven’t seen acollierasto mentioned yet.

She’s a scientist with a PHD in Astrophysics and does deep dives on specific topics, generally from the angle of science communication and how it often fails that topic in some way.

Her videos are very simple and low production value, but packed with information. She’s a great communicator and you walk away from each video, not just with better knowledge on a topic, but also with a sense of where the holes in that knowledge are. Like where the limits of the metaphor being used to covey the topic to you exist.