Sounds like opening a can of worms ... some developers will definitely opt for using a language which has "convenient" properties -- since the generator code is not running on the target platform, it has different constraints. And then one day, another dev team will face the task of porting rexx/perl/python/ocaml/you-name-it on a platform which has no capacities for that, or has no required depenedencies available, or neither.

You are making the error of thinking that one can only use one language, or that using the right language for a job is a bad thing; and you are making the error of thinking that build platforms did or do lack the capacity for generating source like this. These are platforms that have the capacity to run a C++ compiler; they have more than enough capacity to run tools like (say) od and sed.