> If the owner was in control of the kill-switch, it would still have all benefits of theft protection, without the problems that arise with a manufacturer controlling devices indefinitely.

Apple has a similar feature for its devices that is in control of the user, but ultimately it's still depends on the device connecting to the internet and getting a ping that it's "lost" from Apple's servers. There's not really anything stopping Apple from locking people's devices, either.

I just feel like "self hosting" isn't a real company solution to a kill switch, so I'm not sure how you have a kill switch without interacting with the company in any way, even if you're not John Deere.