Sounds like the 2 hard things in Computer Science returning! Cache invalidation, naming things, and off-by-one errors. [1]
* "Knowledge is ephemeral": Cache invalidation
* "tower of abstraction": naming things, indirection [2]
Recommendations:
* "Reduce complexity, reduce dependencies": minimise entropy, maximise connectedness
* Learn: welcome newcomers; recurse to the next generation
[1] https://martinfowler.com/bliki/TwoHardThings.html
[2] All problems in computer science can be solved by another level of indirection" "...except for the problem of too many layers of indirection."