Carbon was a stopgap measure for two big companies (Microsoft and Adobe). It was very clear from Apple's actions with other technologies these companies didn't use (e.g. OpenDoc) and its messaging to developers that Carbon was not a permanent solution. Why people were surprise in the 64-bit conversion to see Carbon absent was beyond me.
Now, Apple has a whole hoard of technologies that Adobe and Microsoft didn't use that did not make the jump from OS 9.0 to OS X. OpenDoc is most famous for the youtube video where the angry developer questioned Steve Jobs. I suppose you could add Newton OS to that list, but it is more the closing of a whole platform.
In more modern times, if you started using GC, then you had to convert to ARC pretty soon thereafter.
Now, Apple has a whole hoard of technologies that Adobe and Microsoft didn't use that did not make the jump from OS 9.0 to OS X. OpenDoc is most famous for the youtube video where the angry developer questioned Steve Jobs. I suppose you could add Newton OS to that list, but it is more the closing of a whole platform.
In more modern times, if you started using GC, then you had to convert to ARC pretty soon thereafter.