Probably gonna get flamed, but I'll post my two cents anyway.
In my opinion, the show was badly dehabilitated when Mike Scully took over. Al Jean rejuvanated it to a point to where it wasn't in perfect health, but was still able to get by just fine. Then season 17 rolled around and the show's health went on the decline again - eventually to the point where it was in worse condition than the Scully years.
In my opinion, most of the Scully episodes are amazing when compared to today's stuff, but that would be like saying a specific person was in great health at the turn of the millenium because their speech and cognition were screwed up - compared to now where they are a vegetable on life support.