He doesn't really fail upward though. He wins a scholarship, he enlists in the military, he plays ping pong for diplomacy, buys a shrimp boat, then moves home. None of that is upward. He shares profits from the shrimp company, he doesn't fail. He's good at football, serves with distinction...
...saving a number of men, he's very good at ping pong and he's even an equitable boss of the Bubba Shrimp Co. Dan invests in Apple (which in 1994 was actually a bit of a joke) but at no point is Gump a failure. You can hate the film but you've missed what Gump actually does.
he’s an idiot and it’s revered. everyone who loves that movie feel entitled to have all the things. fuck that movie
But at no point in the film does Gump fail, and it's never really "upward", he's a soldier then plays ping pong, he runs a single shrimping boat, which expands to a fleet but Dan manages the fleet. He may be an idiot but he works for what he gets. The audience reaction doesn't change that.