I think theirs was the right conclusion, but for the wrong reason. If there was anything really damning, Iran would rather use that as leverage.
The fact that they released it publicly means that the most embarrassing part of it is just the hack in itself.
From the news I’ve read the most “embarrassing” things in his personal email are photos of him smoking cigars, holding a bottle of rum, and posing in front of a supercar. What a scandal…
If I was Iran I'd leak the innocuous stuff first to let them know I had access to potentially more damning things, to try and force the US to the table.