Not true. Apple spends an enormous amount of effort on backwards compatibility. For example, they wrote a JIT compiler to be able to run 68k code on PPC. They did the same for the PPC to Intel transition. They maintained the "Classic" ABI and binary formats for years after the move to Mac OS X.
It is true that Apple doesn't maintain backward compatibility for a long as Microsoft does, but that's not the same thing as not caring. They put the effort into making transitions as smooth as possible for users and developers and getting through them quickly.
It is true that Apple doesn't maintain backward compatibility for a long as Microsoft does, but that's not the same thing as not caring. They put the effort into making transitions as smooth as possible for users and developers and getting through them quickly.