I just felt the ending was too rushed on GOT. You could really feel the cramping of shoving everything together into that last season. There were entire seasons you could've done off of some of the ideas presented in that last season.
They delayed the entire 8th season by a year, and told us the reason(s) were that they:
1) Wanted to give us the best story possible.
2) Didn't want to rush the ending.
3) Were going to make each episode close to feature movie length.
What we actually got?
1) Terrible writing/story. I mean, the entire first 2 episodes (of a 6 episode shortened season) had them sitting around in Winterfell doing nothing but reminiscing and feeling sorry for themselves. Then the big battle happens.........which is a dud. The big baddie Night King dies in the most anticlimactic way imaginable, and Jon is just pretty much ignored. None of the really important main characters get hurt, much less die, despite getting completely destroyed by the white walkers. And somehow the entire Dorthraki army survives, despite getting wiped out on their initial charge into the darkness. The Night King was supposed to be the big baddie, and he's gone by episode 3 of the final season. All that build up over 7 seasons, for that? Dog $#!+
2) See above. They sit around and doing nothing for 2 episodes, then again in episode 4 not much happens. So they try cramming the rest of the story into the last 3 episodes.
3) The episodes come out, a lot of people are expecting ~1.5 hour + long episodes after a 2 year wait. Instead, we get: 54 mins, 58 mins, 82 mins, 78 mins, 78 mins, 80 mins. Sure, a couple of episodes are slightly longer than normal/previous seasons. But 6 episodes total run time = 430 minutes. (Season 7 was 440 minutes total run time, while season 1 was 567 minutes long). The final season was the shortest season in the series, in both number of episodes and total run time.
The final season was a supreme disappointment and utter crap. A few flashy/brilliant moments do not a great season make.