> modern Apple basically wants macOS to go away and sees it as more of an annoyance, so they don't spend any time tuning it
[citation needed]
[citation needed]
And then they keep adding iOS UIs into MacOS, produce horrible laggy iOS-optimised software for it, and call it a day.
Actions speak louder than words.
And yes. Merging codebases is a bad thing when it's done without any care for one of the paradigms. The one that they don't like, don't understand, and want to go away.