[bonton89]

SMS 2FA is only ostensibly about security. Mobile providers always sucked at it and never advertising that they were selling high quality identification services in the first place. They've actually gotten better at it but it wasn't ever there thing and still isn't.

Phone numbers are excellent PII for user tracking though AND allow companies to dump a lot of the hard support work on some one else. Gobbling up PII to sell and externalizing the hard support stuff to some one else is how tech companies and increasingly any company works these days. So it isn't a surprise it isn't going anywhere. You'll likely need to cough up a number at least for "verification" anyway (since they want it) so they'll probably just use that for account recovery to while they're at it to make their lives easier.