I know very well how oauth works, thanks, but I'm not sure why you thought that had anything to do with my comment. The invasion of privacy comes from websites insisting on knowing who I am and refusing to allow me to make anonymous/pseudonymous accounts. If there's a convenient API to do so provided by the government, that's bad for users.
> Only the ones where you chose to use their service.
There are hundreds of websites that require you to use Facebook to log in. With government-sanctioned ID, it will be worse.
> Or are we imaginging a future where this service has been made mandatory, and logins and passwords have been abolished?
This already exists in several countries, including Korea. https://en.m.wikipedia.org/wiki/Resident_registration_number
Hopefully this serves as an indicator that your skepticism on this topic is wildly miscalibrated. There's no "imagination" involved, this is how it is right now in places where this exists.
> their strategy will probably not be writing open source software and hoping you opt in to it!
That is the exact strategy I would use if my goal was to help the government gain more control over the internet. Letting people give their freedom away in exchange for a bit of convenience is one of the oldest tricks in the book.