The article disagrees with your understanding. "Facebook’s default setting allows everyone — with or without an account — to look up a user profile based off th

The article disagrees with your understanding. "Facebook’s default setting allows everyone — with or without an account — to look up a user profile based off the same phone number " For the vast majority of people who aren't on TC/HN, it's a surprise. Once info is leaked, it doesn't get unleaked. It's not just this once incident, it's a pattern of Facebook abusing user trust and chronically launching new features that leak private or semiprivate information by default and destroying the culture of security industry wide by showing users that account recovery phone numbers are not safe to use.