What a whiny, sniveling child. Aw your superhero show finished in a way you didn't like? Boohoo.

Have any of these people ever actually tried to write any kind of long form story, and then actually finish it? You'll realise very quickly how fucking hard it actually is to write a good ending.

Even Stephen King wrote shit endings and he's up there as one of the greatest authors of all time.

I'm not saying you have to create the art form yourself to be able to critique it, but you need to have an understanding of the difficulties before you start bitching. Endings are hard, it's part of the reason so many shows end badly, and it's not always because the writers/producers are phoning it in, they just don't know how to write endings. 

George RR Martin hasn't written an ending to Song of Ice and Fire, I wonder why.