It took years to get (mostly) rid of Carbon. Heck, Cocoa still has the NextStep prefix. The amount of change Apple is willing to make can be hugely exaggerated

It took years to get (mostly) rid of Carbon. Heck, Cocoa still has the NextStep prefix. The amount of change Apple is willing to make can be hugely exaggerated, especially if they're able to control the respective technology (which they do mostly, one noticeable exception being desktop CPUs and GPUs).