Basically, for a long time, the company never really re-evaluated what it had learned and spent time trimming things down, so as a result there is this ungodly mess. At the heart of what the business does, there is no real need for more than a dozen models. So why do we have so many more? Nobody ever refactored away stuff we didn't need any more, and so weird things happen.

There is also a coupling issue that is endemic to all monoliths. We're moving to a micro-service architecture with clean domain separation, and we'll probably go to 1/10th of the code base in LOC terms within 12 months, even if we move some of that functionality into Go, Java or Python services (all options).