Your code reflects the organisation's structure at the time it was written
Organizations which design systems (in the broad sense used here) are constrained to produce designs which are copies of the communication structures of these organizations. —Melvin E. Conway, How Do Committees Invent?
People use Conway’s law in software development to explain how the structure of an organisation ends up being reflected in the structure of its code. There’s even the concept of “The Reverse Conway Manoeuvre” where you decide on the architecture you want the code to have and then structure the organisation to match.
For long live projects like SaaS apps the foundational code was written when the organisation was much smaller and differently organised. There’s a mismatch between the code structure and the organisation. This leads to bugs because of changes that aren’t communicated where they need to be, code doesn’t have an owner to maintain it, and different groups can want to take the core concepts in different directions.
How different is your organisation now compared to when the code was written? Could you do a “Conway Refactoring” to bring the code in line with the organisational structure?