And how long do you think that neat partitioning of keys by country of sale would last? My money is on "until about the next Tuesday after the scheme is first

And how long do you think that neat partitioning of keys by country of sale would last? My money is on "until about the next Tuesday after the scheme is first deployed", and then every phone is open to every sufficiently-motivated country's intelligence agencies and law enforcement, and that's the end of business, law-enforcement and possibly even military security for anyone stuck using one of those devices.