I never sign into sites with a Google or other shared ID, but I've really noticed a great increase in sites popping a signin offer.

You should never share identities across different sites, it's an all-the-eggs-in-one-basket problem.

And Google will use it to track the hell out of you across all those sites, and sell your semi-anonymized identity to ad hawkers.

Steps to disable it here.

https://gadgetstouse.com/blog/2021/07/20/remove-sign-in-with-google-account-pop-up-from-websites/

How to Disable 'Sign in with Google Account' Pop-up on Websites

You might have come across such websites that ask you to sign in before giving you access to their content. If that website is one that you trust and

Gadgets To Use
@johnefrancis I kind of like Apple’s implementation of SSO. Every login gets a unique, hidden email address in the process and apple isn’t in the business of selling info. I don’t use it for anything important, but it’s handy for some sites.
@geektoybox I don't trust Apple any more than anyone else. They'll sell that info when someone can get a bonus for it, which won't be long, if they aren't selling it already and just whitewashing it.