The C++ standard is consistent in how it uses "macro," and it's strictly about the preprocessor kind of macros. "Metaprogramming" is also used in the standard, though not as extensively or rigidly (only 8 times in N4950), but both in the specification and colloquially it's more than just slapping consteval on a function.
There is no reason to encode value computations using template expansion anymore. Even a lot of type level computation can be done via plain function calls and decltype. "Old school" recursive template installation is really only needed when you need specifically the capability to pattern match on types of template specialization.
Libraries like Boost.Preprocessor can’t be taken as an example of “cutting edge” preprocessor metaprogramming. It set a very low bar, and IMO has stifled a lot of developer creativity.
[1] https://github.com/rofl0r/chaos-pp/tree/master/chaos/preproc... [2] https://github.com/rofl0r/order-pp/blob/master/example/fibon...
The reason that they remained niche is that at the time MSVC had an extremely non confirming preprocessor and advanced PP libraries just weren't viable there.
Boos.PP was the most advanced you could get while staying portable.