This is not the full explanation. The key problem here is that C++ runs on nearly everything, from your garden variety x86 to bizarre DSP architectures. The man

This is not the full explanation. The key problem here is that C++ runs on nearly everything, from your garden variety x86 to bizarre DSP architectures. The many, many template parameters are there so you can simultaneously say “you don’t pay for what you don’t use” and provide a library that works on weird systems.