The hacker gaining access to the victim's mobile number technically isn't a "hack". It's more of a social engineering attack whereas the hacker convinces the customer service representative that he/she is the victim. And yea, that's one reason why you shouldn't use mobile numbers as a 2 factor authentication method, as obviously it's quite prone to social engineering attacks.
lot's of things that are unconventional are referred to as "hacks". It doesn't have to be specifically a computer hack. I think you're misunderstanding how they are doing it. They are taking over peoples entire goog accounts.Yes, they can take control over people's Google accounts that's for sure, through the usage of using the mobile numbers they acquired, but I was referring to the actual method how they acquired the victim's mobile number; which is through a social engineering attack. But yea I guess you could also classify it as a psychological hack.
