Those old-school documentaries do not seem to be made much any more. I also prefer them but they are rare to find nowadays. Instead I go looking for lectures on the topic on Youtube instead. Or search for podcasts.

The production cost ratio is probably 1-100 or 1-1000, at least, between the old school, interview-an-expert type, and the dramatized CGI-heavy ones, so it is strange that so much money is put into production of documentaries with so little factual content value.