You're right that the patent is specific to leased vehicles. But that shouldn't be confused with the underlying technology, which would have to be baked into the software of all vehicles, including those sold outright.
This means the vulnerability of remote hacking will exist for all vehicles. And who knows what will be buried deep in the TOS — perhaps in a few years we'll hear about Ford shutting down vehicles for people who attended a particular protest that is not in line with the current social mores.
It's just a matter of time before this technology is used to extract rent on non-leased cars just like subscriptions for heated seats/etc (or intentionally make the full "own outright" model unaffordable so everyone is forced into leasing where they can use this tech).
