i don't think alot of people were really mad about the direction (Mad Dany, Arya stabbing night king, etc) the show is going...the backlash is about the execution. The payoff doesn't yield much satisfaction due to either the lack of reasonable build up or just out of the blue development (Euron Greyjoy fight with Jamie...who came up with this?)
This season felt rush through and through as if they are trying to get to the finish line by checking a list of checkbox with very effort put in the nuances of how the pieces came together.
Why is it 6 episodes? Clearly HBO wanted more episodes and more seasons, not less so budget and the lack of will from the network is clearly not the reason.
The only blame can be laid on the main writers and showrunner, D&D, for seemingly wanting to get off the GoT train ASAP for whatever reasons only they knew (the rumor of them wanting to go to disney to do the star wars thing thus the rush notwithstanding).