I travel, and data plans are way better in some countries than the
plans, and they make sense for longer stays, which happen to me.
So, think of phone numbers like IP addresses, and create a DNS record
to link domains to a phone numbers.
Why? Well, in my experience, it
is quite often that I register somewhere,
then do 2FA verification, and then I lose the phone, because I spend more
than 6 months of not using that phone number.
I'm using a redirect to phone URL and a TXT record right now, but the
systems that send
verification SMS messages don't have a default way to determine that my
phone is tied to a domain name, and we can't make a call by typing a
domain name instead of phone number into phone dialing pad.
Coming up with a special record type for DNS, for that purpose, and
on IETF as an RFC, would it more likely that phone manufacturers and OS
support it, and we would not have to remember phone numbers, like we
have to remember IP addresses.