I can see why people want a phone number now. I was thinking more about why society doesn’t move away from phone numbers (for me, it’s been a hastle to be linked to a carrier and a country)
What better system can you think off? That allows calling the doctor, a restaurant, or that friend-of-a-friend who is selling a tractor?
Without requiring people self-host a brunch of infrastructure (I like self-hosting stuff, most people wouldn't)
i think the problem isn't the phone number, but the special hardware/vendor lock in that is required for it. if you travel a lot or live in a country where it is just easy to cross borders as a part of life, it quickly becomes obvious that being tethered to a regional provider for your phone number is a problem.
you end up paying ridiculous roaming fees to keep your number active in the other country, or you lose any ability for people to contact you by phone. it's incredibly frustrating when voip is so close, but not the 100% solution. couple that with providers still charging ridiculous fees to call numbers in other countries and it gets even worse.
Good question - e.g. why isn't a phone number like an email address.
My guess is that it functions as an anchor - not to help motion, but to guarantee immobility. Like a physical address, the inconvenience of changing makes for fewer changes.
A low-pass filter, for system stability, if you want to look at it that way.
I'm pretty close to skipping out on my cell number. I very rarely use it. But that said, I do use it every so often, and when I do I need it pretty strongly. Also, I've had the same number for something like 15 years, and that's hard to walk away from.