> Provide an example of a manufacturer removing features in "bad faith."

Sure, any app not running because of artificial software restrictions (and no, I won't buy the claims of """security""" when even the manufacturer doesn't have a real picture of what's running on the phone and cannot assess it's security - or sometimes even includes built-in adware!).

Another example of bad faith could be Apple removing true tone on official screen replacement.

Again, I'm not against the concept of chain of trust, it's just I've never seen any software restriction which I would think justified, so a good use case might exist in theory, I'm just not aware of it.

> The other issues to resolve here would be anti-tamper and chain-of-trust concerns that could arise from such an approach

I have serious doubts that integrity checks and anti-tamper mechanisms are legal in the current environment anyways as there's no real competition in the mobile space and these are further barrier to create competitors (and were even created for this purpose in the first place in some cases, like in Android)

It's definitely against current anti trust laws. These companies are just too large and too wealthy for the laws to be applied at the moment.