Why is Google using this anti-pattern sign in feature?

Google has a feature "Sign in with Google" that auto appears on any site that supports it.

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This seems to have harmful UX repocussions?

  1. If Apple, Facebook, and others follow the same pattern we'll end up with this or worse

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  2. It shows up a few moments after the page loads appearing directly under the fingers where you're likely scrolling if on mobile meaning you're likely to click it by accident.

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    Note in the gif above I deliberately kept my finger high so I didn't accidently click it since I knew it would soon appear. If you click it by accident your email address is immediately shared with the site even though you never intended to click it in the first place. Cancelling your account will not help as your email address will already be in their database (and likely already added to marketing emails)

Why would Google use this arguably poor UX design?