Season 12, season 20, doesn't make a difference, it's all the same crap to me now. I stopped watching it full time somewhere around season 11, and catch a new episode every season or so. And every time I do, I just yell at the TV and leave disgusted. I can't even tell when they're attempting jokes most of the time. To differentiate any season since 2000 is just splitting hairs to me.
The voice acting can't even save it anymore. None of the characters sound right, because the voice actors have aged 20 years since they started, and all of the characters have become so one dimensional that they can't rely on the strength of their characters like they used to, and rely on the voice actor's ability to sell the point.
And the writing has become such rudimentary pop culture references, rather than the subtlety they used to have. Mapple? Wow, that is some clever stuff, guys. Some real original social commentary that delves deep.
Now they just have a character say "WWWWWHHHHHAAAAAAAAAA?" to everything, which makes me want to claw my ears out. No good episode has ever had a character say "WHAAAAAAAAAAA" in it.
I'm getting all worked up just thinking about new Simpsons. It's been embarrassing itself for so long that I forget it's even the same show that used to be so amazing. It had the best streak of great episodes of any show, then wiped it out with an even longer run of cringeworthy parody of itself.