About categorical change, I agree... seems like everybody is just busy optimizing stuff invented in the 70s.
But, it's also worth looking at places where there's been enough change of one kind or another to constitute "qualitative". This has certainly happened in many areas of engineering and in science. How about in computering?
But let's see -- how about UIs giving up on UNDO, not allowing or not showing multiple tasks, not having good ways to teach how to us the UI or the apps, ...
And a zillion more ...
Yikes!