Why do you assume Dany becoming dictator was what I took issue with? I agree that that was actually pretty well foreshadowed.
I was pretty clear in the article about some of the issues I saw in the endingd. It was the holes in the writing. As you mention, shock and awe were established early on. There was a sense of stakes. When Ned Stark died and the Red Wedding happened, there was a feeling that no one was invulnerable.
By the time the seventh and eighth season came around, it felt like no one could die. The most climactic battle of the entire show yielded like one or two side character deaths, and the Night King was unceremoniously dispatched by a long-jumping Arya? The smartest character in the show instructs everyone to hide in the crypt? Where the dead people are literally buried?
Dany's dragon was killed because, according to D and D, "she kind of forgot about the Iron Fleet"? They build those dragons up as her babies, and she forgets about one of the biggest threats in the realm they're facing? Jon Snow joins the Night's Watch because... who really knows. All the White Walkers were soundly defeated. Along with pretty much all of the Dothraki, but they magically multiplied into a sprawling army a couple episodes later. The writing is just abhorrently lazy in those final two seasons. And i don't say that as a contrarian. I love the first 6 seasons, and I even love what D and D have done with 3 Body Problem. But there are very, very few fans who found any justice in what they did with those final two seasons.