But being heavily involved in hardware product design? I think that's above his pay grade,
Not as a brand, and surely that's what this is about. Lenovo is trying to nexus Kutcher's appeal outside China to help smooth the path into hearts and minds that may never be tempted to give their (Chinese) brand a second look otherwise. It worked for Nikon, as just one example. They are already enjoying headlines over it.
That, and they may have been forced to classify him as a unique technical asset (true or not), in order to get him on the payroll with Beijing's approval....
I worked inside Lenovo a few years back and I wish them the best today.
You say you are comparing on the same hardware, but there is no hardware in common for all the OSes you state.
Doesn't matter. There is no comparison between disjointed hardware and software on one side, and Apple's start-to-end products on the other. That's what this is about, not how everything out there compares directly. It's also why Apple is able to deliver such stellar battery life across the board.
With your bare hands?!?