The coffee damage was the last straw. I was fighting the language (Swift), the lack of documentation (WWDC videos are not a substitute for documentation), and the general lack of any attention paid toward the needs of small app developers.

I spent a lot of time building my own stuff to render pen strokes because Apple refused to supply an API that gives access to the underlying stroke data. SwiftUI was similarly crippled: developers have no access to internals, which made it impossible to write tests that would inspect the view hierarchy. I understand that Apple wants to retain flexibility with their APIs, but they took away far too much. I have no interest in an expensive platform that treats me like a child by locking me out of everything I actually need from it.