This is already reality in Finland. Want to schedule a doctor's appointment? Bank ID. Want to pay your taxes? Ban ID. Want to check your pension? Bank ID. The worst part of it is that a significant swathe of the population does not have access to bank ID, so they can't access these services anymore. It's a kafkaesque dystopia that is going places that I never thought would be possible.
I am Swedish so I know.
BankID I like as it is now for authority stuff and I understand its need. The alternative would be everyone rolling their own auth and MFA, would be bad.
Now imagine all social media tied to your BankID. This is their wet dream.