Not really answering your questions, but regarding monomorphization, you can see a comparison of code size and compilation speed between printf, std::format and

Not really answering your questions, but regarding monomorphization, you can see a comparison of code size and compilation speed between printf, std::format and C++ iostream. The last one is monomophization, I believe. https://github.com/fmtlib/fmt#compile-time-and-code-bloat https://github.com/fmtlib/fmt#compile-time-and-code-bloat