I'd have no issue with the lienholder having ultimate control of car until the loan is paid off. As I said in my initial comment, that's completely beside the point.
The problem here is that Model 3s are apparently "loyal" to their manufacturer rather than the owner, regardless of who that owner is (whether that be a lienholder, the car's "user", or anyone else that's not Tesla).
That Tesla used that misplaced loyalty to give the car back to the lienholder in this case is irrelevant to my point.