I made several large Cocoa (macOS AppKit, Obj-C) apps in 2004-2018 using the classic Smalltalk-inspired MVC patterns and this was never a problem. Sometimes writing the controller boilerplate was boring, but at least there were no observer loops, it was simple to debug where things happened, and undo/redo were reliable to implement through the framework.

Maybe Microsoft just never was very good at these 1990s style GUIs?