Plugin architecture is one form of it. I was referring to a superset of software that's designed for stripping of system components themselves. Examples are eCos and Windows Embedded configuration. An extreme example is Poly2 project using it for security boost by actually removing code from internal functions. I knew a guy who got a fully functional WinXP box, w/ browser & office software, down to under 650MB by just deleting stuff and seeing if things still work. Now, had there just been an automated way to do that...
"in part because of them having to avoid breaking compatibility in the plugin infrastructure too often"
Backward compatibility often makes it challenging. Should ease things a bit if the software is straight-up designed for stripping at client sites. I'd imagine the interface level would stay fixed, though, for compatibility.
"As it is, they are forced to release OSX yearly in order to match iOS, which in turn has to match hardware releases come rain or shine. iDevices now drive Apple profits, not Mac; OSX stability is sacrificed in order to keep iPhone sales healthy. It sucks, but I don't see it changing anytime soon."
Sounds believable. I'm not an Apple customer so I can't speak to it except to say Mac OS X is definitely a second-class citizen right now for reason you said. Apple themselves push strongly things like tablets to replace the Mac's where possible. Part of a larger drive to keep people consumers instead of producers. But that's another topic. ;)