Ok, that's not trivial to hack, but it's in no way more secure than accepting a few more backup tokens.
Both email and phone numbers have widely known and exploited vulnerabilities that won't ever be fixed (worse if the phone part is only SMS). Requiring both at the same time is OKish, but not any exemplary security.
Both email and phone numbers have widely known and exploited vulnerabilities that won't ever be fixed (worse if the phone part is only SMS). Requiring both at the same time is OKish, but not any exemplary security.