There is only so long a disfunctional, yellow, cartoon family can be both funny and ironically clever for, then the episodes tend to vere towards the stupid to try and keep them funny, and any pretence at cleverness goes out the window.
I think the Simpsons were absolutely brilliant in the beginning, and all of us who are fans must have been caught up short on occasions when one of them has said or done something that we horribly recognise as being a trait of our own.
Frankly, I still watch them because I'm endeared to the characters, but they wouldn't have lasted if the first shows had been of the quality they now are. I just get the feeling that the writers have nothing more of worth to say.