> For instance, in a production language, optimisation of generated code is worth a longer compile cycle, but in a teaching language (...) short* compile cycles are everything and quality of generated code is an afterthought.

I don't think this is a valid take. It sounds like an attempt to rationalize away awful build times from some systems language. C++ has atrocious build times, but in contrast C compiles almost instantly. Other production languages such as C# and Java also have fast build times.

I don't think long build times are correlated with optimization or production-ready code. They are however linked with attempts to get compilers to do a lot of work just to get our code to generate machine code, but some of that work is due to how some aspects of a programming language sucks and require more work just to pull off an optimization.