I see no problem with using phone numbers can be used as an ID. They should not be used for authentication though. For some reason it has become fashionable to

I see no problem with using phone numbers can be used as an ID. They should not be used for authentication though. For some reason it has become fashionable to force 2-factor authentication on users using SMS as the 2nd factor. That is a terrible idea, and yet it proliferates, especially at most calcified institutions (banks, DMV, twitter). This has to end.