In a sense something like 3Blue1Brown or a good DIY channel is almost a modern equivalent in terms of content but the thing these old documentaries (not to be overly patriotic but often British ones) have that most (almost all, really) YouTube videos have is the expertise and creative bottleneck of being made by a proper TV studio.

Bottleneck I say? From limitation and oversight comes restraint and clever tricks, and that is a good way of making good media.

There's a wonderful culture of tradesmen posting YouTube videos of their work.

My most recent binge has been Perkins Builder Brothers, but also check out Essential Craftsman or Samson Boat Co. They lack some of the gravitas of the old guys, just because of their modern tone. But they're great.