>Fundamentally, many inefficiencies were justified for developer productivity, and I'm not sure that makes sense anymore

Having lived through this period, I would disagree, quite the opposite we tended to develop in C and assembly specifically for runtime efficiency because we had to.

For developer productivity you could opt for Lisp or SmallTalk or some such, which ran much slower until high quality compilers for these became available, and even then your target machine might only have a C compiler.