"How Apple could have helped: by running a few queries to update a handful of fields in their database."
It's true that Apple ought to have a process for migrating a developer account from one entity than another, but:
1. The logic in Apple's production code probably depends on some specifics about an entity (e.g. the country it's in) being constant over time. For example, if there's some code that deals with quarterly accounting of revenues and taxes, that code would need to keep track of not just the current jurisdiction, but also the jurisdiction at each point during the quarter.
2. It's not a great idea to 'run a few queries' that update production data, because you (a) could cause an inconsistent application state, and (b) will probably lose the ability to audit past state.
Let's not forget compliance with laws. You can't simply "adjust a few tables" when your historical supplier data is required to be immutable.