It wouldn't forbid shipping the device with a virus scanner. It would only forbid refusing the user control over what software does and does not run.

There might be a couple messy edge cases if applied at the software level but I think it would work well.

Applied at the hardware level it would be very clear cut. It would simply outlaw technical measures taken to prevent the user from installing an arbitrary OS on the device.

Regarding warranties, what's so difficult about flashing a stock image to a device being serviced? At least in the US wasn't this already settled long ago by Magnuson-Moss? https://en.wikipedia.org/wiki/Magnuson%E2%80%93Moss_Warranty...

> what's so difficult about flashing a stock image to a device being serviced?

Yes, I think that would cover most cases if we take it to its logical conclusion of wiping all device state (hard disk). OTOH, a few points:

1. I would accept the need to wipe the hard disk if I had messed with firmware or the OS, but not if a couple of keys on the keyboard had stopped working. This implies that (for me at least) a meaningful distinction remains between these two "levels" of warranty service. Do you agree?

2. Activities like overclocking or overvolting a CPU have the potential to cause lasting damage that can't be reversed by re-flashing. Under the policy you're suggesting, it would be illegal for manufacturers to offer users the option "You can pull this pin low to overclock outside the supported range, but you will void the warranty by doing so", and too expensive for them to endlessly replace parts damaged by these activities for free under warranty, so that consumer option, rare as it already is, would go away completely.

3. I still think there may be some devices that are impractical to completely re-flash. According to this 2021 Porsche article [0], modern cars contain 70-100 ECUs (microcontrollers), each of which will have its own flash/EEPROM.

[0]: https://medium.com/next-level-german-engineering/porsche-fut...