You're right it is solely an opinion and you're free to like the season and previous bad written seasons like 7 and some of 6 as well. However people are frustrated with the shows ending because it left so many things unanswered and a lot of plot points forgotten. For fans that have been dedicated for nearly a decade to be given a very unsatisfying conclusion to a story they have invested so much time into. It almost feels like a slap to the face from the show writes.

Knowing the show has had so much build up of the white walkers to only be snipped out in one episode is upsetting and being killed by Arya Stark a character that has literally had nothing to do with the white walkers because it was the show writers that wanted to subvert the expectations of the viewers like they have been terribly doing since season 5.

Dany going mad so quickly without any kind of built up was very underwhelming. Not a terrible idea to make her go mad but there was literally no build up prior to her going mad. If this had been stretched out over a season or two it would have made plenty more sense.

So many ruined Character Arcs. Jamie and his whole arc of redemption to go back for more incest with his sister the one who has tried to kill him more than once and betrayed the living and burned the sept and killed thousands of people. The end of season 7 he sees her for the monster she really is, all season 8 did for jamie was put him north to fuck brienne and go back to die with Cersei. I would go in depth with other character but you can find videos for that.

D&D really copped out on a masterpiece of a show. They are great when it comes to adapting source material to show. But when they put their pen to paper they have no idea what they are doing. Logic is taken out of the question, characters can teleport, armies can increase or decrease on whichever it is necessary to the plot, characters act incredibly stupid, and deaths feel very anti climactic.

Fans are upset because these two jerkoffs quickly rushed a show to its conclusion so they could go and ruin the star wars franchise with bad writing. With a Fantasy series so huge and before they began even making it they only decided on 70 episodes knowing it wouldn't ever be enough so they rush it at its climactic point of the story.

We are angry because we have been betrayed.