Apart from Google sponsoring this in some way or the other (by boosting up SEO ranking in sites that display this) I believe that this is a consequence of the third party cookiegeddon and I guess that once your users allow this login their activity is tracked as first party in your website, which would simplify things a lot for, well, tracking user behaviour. Of course Google benefits more.
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Apart from Google sponsoring this in some way or the other (by boosting up SEO ranking in sites that display this) I believe that this is a consequence of the third party cookiegeddon and I guess that once your users allow this login their activity is tracked as first party in your website, which would simplify things a lot for, well, tracking user behaviour. Of course Google benefits more.