The problem with this claim and then the legal cudgel that it buys with these claims is that they always have been demonstrably false and now this has ratcheted up into attempts to bar obvious design features that Apple did not invent from being sold by anyone but Apple.

What has Apple actually "innovated" in?

One thing: cult consumer behavior. There it has indeed innovated.

The company stole Xerox PARC's ideas (specifically the Star workstation) when it came to the mouse and graphical user interface. It did not invent any of those features -- not windows, not icons, not the mouse, none of it. None. Utterly none.