Earlier quoted context omitted.
That could be said for any platform these days. It's certainly not specific to Apple!
I guess Windows doesn't break their compatibility almost ever. Linux doesn't break user-space, but of course the libraries you depend on might change in a few decades.
What is claimed to be backwards compatibility is only partially true; reality is that bugs and their workarounds will exist forever.
As for Linux and breaking userspace, that's the kernel interface which is stable, not the whole distribution. I really wish people would report that honestly. NT's API is stable too. It doesn't mean Gtk and ComCtl32 doesn't have abhorrent stability problems and bugs in them.
The issue is, on all platforms, the thousands of libraries each containing hundreds of calls and data structures.