After hours of searching I've got a fairly substantial playlist of some 80 videos, with a combined runtime of around 100 hours, ranging from TV documentaries to academic talks. I've avoided any UFO/alien related ones... Enjoy! https://www.youtube.com/playlist?list=PL7PX-HjvtKk0DaHOGm729deZS5mZ6kbBX
Excellent! Most of the talks like those are from Penn Museum, the film and sound quality can vary on the older ones but most are very watchable.