If this were being offered as a second factor, it'd be good. As the only factor, though, it's crap. I can (and do) lose a phone much more easily than a secure password. Now you can use Android phones, rather than passwords, to log in to Google* https://arstechnica.com/information-technology/2019/08/google-lets-android-users-skip-the-password-when-logging-in/