Apple

That's a big part of the problem though... it's Unix. The BSD-based underpinnings of Mac OS are just different enough to be a colossal pain in the arse for interoperability with GNU-based systems.

At a surface level things seem similar enough, but that people seem to think developing on Mac and deploying on Linux is this simple process really confuses me, because every time it's come up in my career nothing has ever worked properly. Every occasion a bunch of time wasted finding the one little difference that breaks on one platform (and I'm going to be blunt here; it was always on the Mac).

For my money too, the Mac UI features some of the most incomprehensible and borderline unpleasant design decisions. Window management is downright infuriating. File management feels barely functional. Apple's stubborn insistence in hiding the options they'd clearly prefer you didn't use (to make using it actually pleasant) in "accessibility" menus is baffling.

Some of this stuff harks back to last century. I hated the way things worked back then in Mac OS 6 on a Mac classic, and a lot of it they still haven't fixed.