Well I can't speak from the point of view of a mechanical inspector, but as a consumer, MY experience has been the opposite. Diesel trucks have been FAR more reliable than their gas counterparts doing the same job.
As a contractor, I use my vehicles fairly hard. They are not just commuter cars or grocery getters, though they do that too. They carry and tow thousands of pounds daily, 6-7 days a week.
I've owned 6 diesels now since 1997, all were Fords, all were either 7.3 or 6.7 powerstrokes. None had any problems that weren't directly caused by my right foot and a healthy dose of extra HP.
The only extra cost I incurred owning diesels over gassers was the lure of easily gotten HP and TQ from a simple tune and some bolt on parts!