In my case I had a recovery email set for my account and knew the password. I didn’t have any 2fA on but when I would try to log in Google just decided it didn’t recognize me and I needed phone verification - it wouldn’t use my recovery email. I had lost access to the number they were trying to use so I am forever locked out. I’d even get attempted login prevented emails at my recovery email.
Similar experience with one of my accounts and it seemed totally absurd that me giving them a phone number that has never been used for the account somehow verifies that I am the owner. It's clearly an attempt to extract more data from a desparate user.
