Compiler writing has progressed a lot. Notably in meta compilers [1] written in a few hundred lines of code and adaptive compilation [3] and just in time compilers. Alan Kay's research group VPRi tackled the problems of complexity (in writing compilers) [4].
[1] Ometa https://tinlizzie.org/VPRIPapers/tr2007003_ometa.pdf
[2] Other ometa papers https://tinlizzie.org/IA/index.php/Papers_from_Viewpoints_Re...
[3] Adaptive compilation https://youtu.be/CfYnzVxdwZE?t=4575
the PhD thesis https://www.researchgate.net/publication/309254446_Adaptive_...
[4] Is it really "Complex"? Or did we just make it "Complicated"? Alan Kay https://youtu.be/ubaX1Smg6pY?t=3605