> for the owner to be allowed to permanently disable unlocking, e.g. the commonly cited example of someone setting the device up for their elderly parents

This opens a wormhole that warps us back to one of the core issues / battlegrounds in computing: ownership, and specifically, the balance of power and responsibility between the owner and the user, when they're not the same person.

Unfortunately, the same means and the same arguments cited in case of "someone setting the device up for their elderly parents" also apply to employers "setting the device up" for their employees (where "setting the device up" may just mean letting it access the company network), vendors "helpfully" "setting the device up" for the customers (this is basically the whole history of mobile phones - bootloaders now, SIM locks before), etc.

I don't know what the good answer is. I'm personally strongly biased towards "end-user should always be the owner" perspective, and while I recognize there are strong examples where this isn't the case, I can't figure out how to cleanly separate "legitimate interest" from for-profit or for-power abuse.

It seems relatively simple to me. Only the owner is allowed to make these decisions, more or less. Employers can only do it to devices they own and provide. Phone vendors cannot do it, and cannot make any services contingent on doing it. A family member in this situation is reasonably acting on the owner's behalf.

And while we're at it, let's not allow apps to refuse to run because of rooting.

The balance of power between a company and you, vs you and another person, are vastly different, which IMO makes the issues distinct. Presumably the elderly parents are willingly relinquishing control to someone they trust, and they can always go out and buy their own phone if they don't want that.

In that scenario I think employers should have the right to make this decision since they own the device and it likely contains sensitive data and credentials belonging to them. But vendors selling devices to retail customers shouldn't be allowed to make that decision unless the customer explicitly asks for help.

I think it's pretty consistent, whoever legally owns the device should be allowed to decide what is and isn't allowed to run on it.

Yes, my point is that in practice, this gets abused. In particular, the possibility enables vendors to invent business models that rely on denying users ownership, and those happen to outcompete the fair, honest models.

> factory reset the device before unlocking it to protect existing data (like Android phones require)

I never understood this point. From what threat is it protecting the data from? Surely a thief should not be able to unlock a device without first typing the correct pin/password, and it they can do that they should be able to access the data regardless.

In principle I agree but the edge case I think has to be accounted for is that many people have weak PINs protecting highly sensitive apps (financial, banking) on their phones like that could be backdoored with root access.

There have been times when I really wished that I could OEM unlock my Android device without wiping but overall I think I sleep better knowing that my PIN isn't sufficient to extract all of its data.