While what you're saying might be true, I can't help but think about Pascal units and say: "It didn't have to be this hard! We solved this problem 40 years ago!"
Which is a language I absolutely adore, and am building a homomorphic encryption based product leveraging Hyperledger on a rather obscure 160 hardware thread POWER8 server; it can definitely work for real production tasks today, even if some parts are rough (and hell, C++ can be rough too). Parallel compilation on this machine is stupidly quick :)
Sorry, it's the same in Delphi (Pascal successor). The compilation time goes up exponentially as number of units goes up. Compilation of 2.000 files (750.000 lines) takes about 20 minutes.