User account associated to a phone number is a common tactic. Phone numbers serving as a proxy for identity is more and more of a thing. People might talk abou

User account associated to a phone number is a common tactic. Phone numbers serving as a proxy for identity is more and more of a thing. People might talk about burner phones, but many localities never really had burner phones in the first place (Japan doesn't give a phone number on travel SIMs, there's "no way" to have a phone number without getting your ID checked somewhere), and other localities are tightening the grip on this. It's not a universally nice and open solution. But it's probably one most markets will bear