They do ask if you want to update now or wait + tell you that the car won’t be available for x amount of minutes.
It's a very software idea to ship things unfinished and fix them later. At best it's annoying, in a car it's dangerous.
I expect when I buy a car that the manufacturers have spent time thinking about the layout, and they've got it the best they can, ironed out the bugs etc. I don't want to come in in the middle of an iterative process. I don't want buttons moving, I don't want 'improvements', I want to buy an actual functioning car from day one. One that the manufacturer is happy to stand by from day one, and they don't feel entitled to 'improve'.
Also, who is buying such expensive cars without any idea how they operate?
But I agree about the horribleness of the UI changes - I still hate whatever the UI update was that went out like a year ago and haven't figured out why they actually did it.
Seriously I would probably remove the antenna or the sim card for the car's data connection.