I will say that, as someone who knew the above mentioned hacker when I was underage, ATT and Verizon methodically train their employees on pretexting and other social engineering attacks. While they may have their flaws, they both have a culture of security and privacy that is completely different from TMOB.
There was a Darknet Diaries episode recently[0] that focused on a guy who frequently did phone scams, and he said Verizon was the most expensive to hack because you had to basically pay a bribe to get into their systems.
Webmail providers don't even have service, which can be a curse as much as it is a blessing
Anyone can commit megafraud against you by filing a USPS change of address form on your behalf to intercept all your paper correspondence, not to mention the rampant straight up package theft the past few years.
We need a more comprehensive plan than just 'dont use phones'. As long as correspondence has value, someone is going to try and steal it.