I've noticed this a lot too lately, and the more I thought about it, the more I find Netflix to be the main culprit here. They fund these "documentaries" which are beautifully done and paint a wonderful narrative, but are ultimately empty of any meaningful analysis or content. Don't think they are doing this on purpose though, it's more likely just a side-effect of their content dump. PBS, BBC, and NatGeo documentaries are still interesting and relevant, imo.