There's no catharsis or payoff in anything that happened in "The Long Night." Yes, it was cool to see Jon and Dany tearing through the sky on their dragons laying waste to the army of the dead with massive gouts of flame. But this episode felt weirdly self-contained, like everything that's happened leading up to it didn't matter. Every fan theory I've seen about the battle with the dead--whether it's a theory from the books 20 years ago or from Reddit last week--is immeasurably more interesting than what actually happened.
One of my favorites until now was that the Night King wouldn't actually show up at this battle--that the attack on Winterfell was a feint, and he was flying to King's Landing to roast Cersei on her throne. There was a ton of evidence for it, but it still would have been a shock. And even better, it would have fit that ultimate series theme--that the fight for the throne was a petty squabble, and the people who failed to see the big picture (i.e. Cersei) would pay a price for it. Instead, the Night King took the bait at Winterfell and died like an idiot. He took his entire race with him, and we never learned anything about them besides "White Walkers=bad."
There are so, so many things that will just never be paid off now. Dany unified the Dothraki tribes and brought them to Westeros so they could die, one and all, in a single ill-conceived charge (seriously, what was the strategy there?). What was the point of Melisandre's entire storyline--the Lord of Light, the resurrections, the Prince that was Promised? Was it really all so she could light some swords on fire and tell Arya to go stab a dude?
Even within the confines of this episode's story--Night King is just a dumb Big Bad Guy after all, he comes to Winterfell, he gets killed--there are endless more rewarding ways it could have gone down. Remember when Dany magically survived Khal Drogo's funeral pyre in Season 1? Now imagine Jon hadn't told Dany about his true identity last season, and instead she had realized there was more to him than she thought when he stepped into her dragonfire, unharmed, and stabbed the Night King in the back. Or it's Arya--but instead of nonsensically jumping onto the Night King's back, she employs her Faceless Men magic to pose as Bran. Bran stabs the Night King, removes his face, bam, it's Arya.
That's payoff. This was boring.