Also, if I understand this correctly, his customers most probably had a copy of the emails on their computers so their loss was only the email address (and emails eventually received after the closedown).
his customers most probably had a copy of the emails on their computers
Based on the fact that a number of them are talking about having lost data, I suspect that at least a significant number of customers only used webmail to access their accounts, so they never had a local copy of their data.
It's still showing not encrypted on the screen which allows all sort of possibilities when done on a browser. For example, let's say you're using Chrome, hard to make sure page contents are not being used somehow.