This is broken, because you absolutely know Google will keep your phone # around and linked to your account, even after deleting it from the UI. No U2F for me, cause Google has to know my phone #.. except I don't have a phone, cause I'm deaf.
Being deaf doesn't preclude you from having a phone, especially a smart phone, which has plenty of applications that do not require sound and many of which actually have accessibility features for the deaf.
True. I use an iPad mini instead, easier for me to communicate with other people, since it has a much larger screen to type on.
They have your phone number if anyone with an android phone has you in their contacts.
If he doesn't have a phone -- and, thus, no phone number -- it would be quite difficult for Google to extract it from someone else's contacts, no?