All usability comes down to what you're used to. I can't use Mac OS because I don't use Mac OS. Sit me down in front of a Mac and it is practically useless to me, nothing works right, same thing with iPhones. They don't "just work" for me.

This is not to say I couldn't learn, if forced to. That's what happened when I started using windows, Linux, and Android after all.

For general usability you need agreement on one way of doing something. Cars are this, you can drive pretty much any car because of the standard way the interface is put together.

My main issue with people responding to any criticism of Apple is that Apple fans (especially hardcore) can't accept that the Mac OS/iPhone interface isn't perfect and doesn't work for everyone.

Mostly agree. IME it really depends on the person. And Microsoft has valued backward compatibly and pragmatic solutions almost to a fault at times. I'd day that's been changing since Windows 8. Still as a DOS-then-Windows native I appreciate their approach.

Job's insistence on a one button mouse for decades, then a one button phone bordered on the absurd as devices grew in capability. Yet it did serve a portion of the market well enough. Even if it kept advanced features virtually impossible to discover with being taught. Doubtful my boomer parents will ever learn swipe gestures, yet my 4yo is doing them now.