Hi Tony,
No way. Probably because it’s the easiest, they choose C.
Korg settings are amazing. As long as you have the correct setting for the track you can record in whatever key you want.
I did a lot of experimenting years ago when I had the PA800. I deliberately set each track to a different key, ie bass key of c , guitar key of d, etc ( they were recorded in the keys I set them too , of course) couldn’t listen to it whilst in record mode, because of the different keys, but once I saved as style, it played back perfectly. All to do with the settings. Each track worked off it’s own key.
Not something one would normally do, just wanted to see how far I could push it.

Yamaha has a heap of settings also, haven’t checked into those. I have my doubts it’s as sophisticated as Korg, but I could be wrong.