This would not fly in Europe. You would be able to return the car for having lost crucial functionality, at least within 2 years of the sale (in some jurisdictions, 5 years). They could do it after that, but functionally forcing a subscription to get back a worse version of the functionality one already had for free sounds like a bad way to encourage sales of said subscription.
Sony is deleting 551 movies from customer accounts, movies those customers paid for. Nothing digital is ever truly yours. They can and absolutely do take things away after advertising them at sale. This is actually quite common.
I’m not sure it would be legal for them to remove something they actually advertise as a feature to sell the car.
Also I’m sure they’d be hit with a class-action lawsuit immediately if they tried it. Manufacturers sell a lot of cars which would lead to a lot of pissed off owners.