As a kid, I used to love "The Adventures of Jimmy Neutron: Boy Genius". Now that I'm an adult, I realized that it wasn't that great.

The "romance" between Jimmy and Cindy felt extremely forced, characters like Sheen and Hugh got more attention due to their meme status, each episode had a handful of plot holes, and the lessons are very heavy handed (The worst example being "The Trouble with Clones" where it had a heavy-handed lesson about spending more time with your friends and family).

But my biggest gripe with the show is that it didn't have any clever writing or scientific accuracy despite being a sci-fi show. I know you're supposed to have fun while watching a TV show you like but if that show puts more focus on the comedy and less on quality writing, then you're not gonna have a good time with it.