Identification numbers should change
Her Britannic Majesty's Secretary of State Requests and requires in the Name of Her Majesty all those whom it may concern to allow the bearer to pass freely without let or hindrance, and to afford the bearer such assistance and protection as may be necessary.
Seven odd years ago I lamented the UK identity system after becoming a victim of fraud.
After some experience with other identity schemes, I've actually started to think the UK system is the best.
Why? Because your identity number CHANGES when your passport is renewed.
"Key rotation" is a good thing. It allows you to start fresh and actually shrug off any compromise.
Compare that with almost every other identity scheme in the world where you are stuck with a number you cannot change. A static identity hanging around your neck like a noose.
However there is a con of an identity number changing in some countries. For example in Malaysia EVERYTHING hinges on an IC number. For foreigners in Malaysia this is your passport number. If your passport number changes, the whole system comes crumbling down. Your credit score is reset. You almost should apply for a new contract for just about everything.
And despite this, it's still worth it. Well done Britain.