I don't watch much TV so I haven't seen a second of most modern day shows, so all I can really lend my opinion to are old cartoons that I used to watch. For instance:
Later Rugrats episodes were sorta like SpongeBob now in that they were forced drops of milk from a cash cow long past its prime.
Rocket Power is laughably horrible. The only good thing it had going for it was Tito, little cuzes.
Pokemon is like the games in that it's always the exact same thing, except the games are actually enjoyable.
And so on...
While I agree on the main point that the show is far past its glory days, I've read that Hillenburg isn't as closely involved with the show as he was originally and that he wanted the movie to be the series finale. (which it wasn't due to $$$) And this might be a bit nitpicky but Joe Murray was the creator of Rocko; Hillenburg did work on the show, but he wasn't the creator.