Listens to Baroque while coding murder.exe :newt: (npub1wc2…4sk7) no internet gimmick can beat phone numbers imo. You cannot be connected all the time and online all the time. I know you can make a case for XMPP and OpenID doing the same things as phone numbers, and get some of the latter's drawbacks applied to the former as well (cost, coverage etc.). But the reality is that the majority of the people have gotten used to talk on the phone more than messaging each other. If there's an emergency, you don't send a message over the internet to someone - that person might not even be online. You don't message 911 (or 112 here, over the ocean) if there's a car crash or whatever, you don't send it messages, you don't email them, you call it.
Messaging over the internet is what? A few decades old? While we're able to call people for more than a century.
Most of us surely remember the time when we were sending phisical letters to each other or postcards - that time is really not so far away in history. It is only a decade or two since email got established.
But I do get your point about apps requiring you a phone number. It really was convenient at first, as you were able to use some services without using an extra thing you had to remember (i.e. a password). But nowadays it's gotten intrusive already. I don't want to use my phone number for everything.