There are basic rules for coming up with these types of product subscriptions:
- Is it something a large number of customers can't live without?
- Is it something that costs money to support and continue developing? Subscriptions help defray that cost and loyal users are happy to keep it going.
- Will the feature be actively used on a regular basis, going forward?
Now apply these to seat warmers, suspension adjustments, self-driving, or whatever else shows up in the future. If you don't hit all three, head back to the drawing board.
P.S.: This isn't limited to cars. It's equally true for any hardware product.