[tuwtuwtuwtuw]

Alright. Where I live, phone numbers are public info and not secret so here they are not used when authenticating yourself against a bank or similar.

Using a phone _number_ to authenticate yourself against the government seems completely bizarre to me.

I understand that leakage of phone numbers become a problem if you use them for those kinds of things. But honestly, using them for authentication seems crazy from a security point of view.