Granted. Convince me this is an issue best solved by a law specifically regulating side loading?
I don't see Apple planning to stop restricting users rights anytime soon. Same applies for phone manufactures who sell android devices.
We don’t force appliance makers to allow side loading. We don’t enforce car makers to support engine warranties if you re-chipped your ECU. There seems to be no “user right” to receive ongoing support at manufacturer expense for a thing the user meddled with outside of parameters.
Along the ‘convince me’ lines:
1. Convince me the iPhone is not an appliance competing in a marketplace of appliances.
2. Convince me the market cannot decide what it wants this appliance to be able to do or not do.
3. Convince me a maker has no right to decide what user actions may void its future obligations to the user.
That's a completely different thing. This is a question of a manufacturer having complete control over what the buyer can do with the device. There is no "click here to void your warranty and enable root" button, if there was this would be a different conversation.