disclosure: I work at google

The thing you have now communicates that yes click over the internet. This new thing communicates through a local channel (bluetooth).

Communicating over a local channel prevents phishing.

Consider this attack: Attacker hosts googlee.com and you get tricked into going there. The login site looks exactly like the google site. You type in username/password just like normal. In that moment they take your phished credentials and pass it to the actual google server, like a man in the middle. Now you receive a prompt on your phone asking Yes/No. You click yes, okaying the attacker's login.

Now that same attack with the local channel communication - they can't take your signal and pass it on through to google