I fear that's a double-edged sword. It'll build a tracking dependency for the parent (which is likely not all that "healthy"), and a similar "I'm being tracked, they don't trust me" fear in the kid, which is also likely not all that "healthy." I'd appreciate the ability to remotely turn on tracking in case of emergencies (ie. kid said they'd be home at 10pm, it's 10:30pm and they're not answering the phone), but having it on 24/7 and relying on it just seems wrong. That kind of location sharing can already be done via smartphones, but having a secondary layer of that in the car would be an added plus (phones can get lost, stolen, etc.).
Maybe I'm just being cynical, but it seems to me that trust (going both ways) is part of growing up. So is making mistakes.
I mean, do you give the kid 50% power? 70%? At what point, after which KPIs, do you "upgrade" the kid from 50% to 70%, or to 100%? Just seems like a whole lot of headache and complication. Trust is either there, or it's not.
I always bought my own vehicles (cars and motorcycles), paid my own way, made and paid for plenty mistakes, learned tons along the way. I think there's a lot of value in making your own way.
I distinctly recall sitting in a grade 11 class with another student, while he had his head down in his arms, looking sad and broken; he then explained that his parents offered to buy him either a new Acura TL or a new 3-series BMW, and he couldn't make up his mind for a week at that point, so he was "depressed." Don't know how that kid's life turned out, but I'm pretty sure we had different challenges & values...