> Metaprogramming style in C++20 only has a loose relationship to previous versions. It is now concise and highly maintainable. You can do metaprogramming in the old painful and verbose way and it will work but you can largely dispense with that.

This was my takeaway as well when I revisited it a few years ago. It's a very different, and IMO vastly improved, language compared to when I first used it decades ago.