Just like SQL, it suffices to rule on one specific use case to keep being used.
I get a bit annoyed by Fortran advocates complaining about people using C++/Python instead of it, when there aren't libraries for doing really basic things. I think Fpm is a really good step in the right direction though.
To be honest reading https://github.com/fortran-lang/fpm/blob/master/src/fpm_back... the only thing look like the old fortran I know is integer I j and do loop. No go to I guess.