the problem with code is that the abstraction changes and data needs to be migrated:

e.g. a user is enabled if they have paid... time passes... now a user is enabled if the team they belong to has paid. now you need to move the logic to another struct / class and the data to another table.

now this is where "payables" and things come in and you start going the path of clean code with 1000 classes.

instead, the best way to do this is immutable data streams and event listeners.

after over a decade of programming, i feel for most software with a customer focus (not low level, embedded etc), immutable data streams where data flows through and listeners do things to themselves is the best way.