With all the stuff Apple has led on with pushing new tech (floppy drives, USB, no floppy drives, etc.) I don't think we should be surprised they've missed sometimes. One might argue that happened with ADB and even more with SCSI. The Cube was an elegant flop. The biggest issue with the 2013 Mac Pro wasn't that they missed it (they thought external ports would be where expansion happened IIRC), but that it took them so many years to admit the mistake and replace it. (It was innovative, but wrong.)
Don't get me wrong, Craig. I agree with you, I don't want it to be a blip. I love having my studio in a box (or two counting the interface), and would hate it if that went away like you describe. I can do some cool recording stuff on my iPad and they've taken steps to make Garageband on iOS and Logic Pro work together, but I'd hate to see this tech crawl away from lower end computers.