I really like Super Eyepatch Wolf's videos. I should agree that Simpsons started to fall off somewhere in the late 90s. But I personally still quite enjoyed an episode like the one where Skinner turns out an impostor. For me, it stopped being funny with the episode Tennis the Menace, at which point I found the characters to have grown so far away from what they had previously been, that I just couldn't root for them anymore.
For me, Simpsons was on a winning streak throughout the 90s, and could be divided into three periods of splendor: the early 90s, when it was an ironic send-up of family sitcoms and the American family nucleus; the mid 90s, when it was a biting satire of American society in general; and the late 90s, when it was a streamlined joke-a-minute show that brilliantly poked fun of both society, world issues, and the media and showbiz. From there, it either had to evolve with changing society, or atrophy. Sadly, it did the latter.
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