I think it's OK to experiment with new forms of monetization, as long as you're not ripping off customers. Here in Berlin VW e.g. operates a car-sharing service using a fleet of ID.3/ID.4's, where you simply pay for a car by the minute, with two different prices for driving (20-30 cents/minute) and parking (9 cents/minute). You can simply drive and then leave the car on any public parking spot (no payment necessary). Often, cars are located just 2-4 minutes walking distance away. I used that so much, but unfortunately VW seems to have decided it's not profitable enough and they recently sold it off to a competitor with worse pricing.

So I guess subscriptions alone don't cut it, you still need to sell the car as well. That said I heard from multiple people that car manufacturers earn most of their money with the service and spare parts for cars (not sure if this is still true) and that the buying price is even slightly subsidized. So from that perspective adding a subscription on top of the purchase price makes sense. In the end people will decide whether it makes sense to pay for that, and I think there will be enough competition in the premium segment, so consumers can just chose to take their money somewhere else if an offer is not good.