I'm on other hand surprised just how decent they are considering they are form nearly 2000 years ago. Ofc, they are no Dutch Masters, but still not too bad. There are worse artists now...
These frescoes were painted at great expense on behalf of an elite figure. He could afford to have expressive art if he cared enough to demand it, and was perceptive enough to recognize whether he had it. Evidently he didn't, or wasn't.