What happened to John Landis in 1990?
In the late 70s and through the 80s, Landis hit jackpot after jackpot with his movies. "Animal House", "The Blues Brothers", "Trading Places", "Spies Like Us", "Three Amigos", "Coming to America"... all funny, all rewatchable. In fact, one can make the claim that Landis was the go-to-man for American comedy of the 1980s. (At least behind the camera. In front, we all know the discussion begins and ends with Steve Guttenberg.)
And then... Oh boy. We beg you not to look what Landis has turned out since. Two words: "The Stupids". That's the one with Tom Arnold... you know, never mind. We don't need to explain it. What's the opposite of "good"? It's that.
So what happened in 1990?
Sylvester Stallone wanted to do a comedy. The result was Landis-directed "Oscar", starring Sly as the titular mobster in a 30s-set slapstick farce. It's been all downhill since.
At least he didn't stick around for Stallone's "Stop! Or My Mom Will Shoot"...