Sorry to bang a drum again…
Data security is certainly a very big concern. But I genuinely think it’s a lesser concern than the purpose of ID cards.
We all have to prove who we are in many situations. But that’s about using a service (state or private) or making a transaction. We already have passports, driving licences, birth certificates, NI numbers, utility bills and the rest of it.
The only reason for an ID card/digital identity would be for it to become an offence not to produce it on demand to police or other law enforcers. Otherwise there’s no point in it. If I have to prove who I am I can do that without an ID card.
ID cards don’t in themselves enable anything or protect against anything in any way we don’t already have. It’s the rules and demands that come with them that they’re created for, and that are so objectionable.