Physical copy since you could get it earlier and play it. Also I like having a physical copy to look at, the Cover art is really pretty.
But from a practical standpoint a digital version is better, because you don't have to swap games if you want to play.
I'm going all digital on the switch, but even if I wasn't I'd go digital for AC.
A game like BOTW, you play a lot until you beat it, and then only occasionally. Not a lot of switching carts most likely. But AC, you play a bit every day, then you might switch to another game like an RPG or whatever. Digital makes that easy, cos AC is always on your switch.
Umm, what? Digital isn't delayed if that's what you're thinking. It will be available at 9pm PST, while Target is closed before midnight. You'll get digital early.