[s_kilk]

My theory is that the show started to decline after about eight or nine years on the air, which is just about enough time for young fans to grow up, go to college, start their career in writing, and then end up on the Simpsons team.

The last person you want writing on a show like that is a life-long super-fan.

[probably_wrong]

I cannot say whether your theory is correct or not, but your theory resonates with something director Hayao Miyazaki said[1]: that the Japanese animation industry is suffering because the staff of a modern studio is full of people who grew up watching anime rather than looking at real people.

[1] https://www.escapistmagazine.com/news/view/131872-Hayao-Miya...

[egypturnash]

This is a good theory. Just look at the shitshow superhero comics have become after a couple of cycles of this.