Look on the output of the “rpm -E %cmake” and you will find that to switch to other C and C++ compilers all what you need to do is redefine %__cc and %__cxx macros,
The same is with %configure and %meson,
In other words you can switch NOW from non-root account to other compiler without execution update-alternatives from root.
In other words this proposal is pointless.
kloczek
--