How would you rank this season amongst the worst final seasons of all time?
I rank it below the final season of lost.
Usually TV series go through a gradual decline in their later seasons, and I stop watching before they end. For example Dexter, True Blood, the original V series. I hated the Walking Dead from the first season.
But most of the time TV series are not really headed anywhere in particular anyway, so the decline is just kind of inevitable as the idea of the show runs out of steam. It doesn't really affect your enjoyment of the early seasons.
Game of thrones is kind of unique in the abruptness of its decline. Granted, the cracks were already showing in season 6, but that was still a great season. And season 7 and 8 are 13 episodes in total, so really they are barely more than a season in total episodes. The Winds of Winter has a 9.9 rating on IMDB. It had a geniunely shocking event that you may not have seen coming, important characters died. It was built up to through 2 whole seasons.
Then a mere 9 episodes later the show has degenerated into its current farce. I really can't think of anything that compares to this abrupt collapse in quality.