I’m sure they were encrypted. But attackers have the vaults and many people have bad passwords. Brute forcing these days is less about trying every combination and more about trying all known leaked passwords, because people reuse passwords like crazy and also just aren’t as original as they think.

If you have millions of password vaults, I’m sure you can crack open a small number. And the ones you can crack are probably the most likely to not be following best practices, meaning it’s more likely they haven’t changed their passwords since the breach was announced a while back and they probably are less likely to have 2FA.