Tyrion even gave a little speech about it at the end. Dany crucified people, she burned them alive, she told people yield or die, it goes on and on over multiple seasons. You can't say that what she did was right because those were "bad people." You have many choices when it comes to dealing with criminals, starting with a justice system and courts that deliver just punishments. Dany skipped all of that and murdered people, in horrible ways. Those are not the acts of a benevolent ruler.

She was clearly someone who started from a good place but whose genetic heritage sent her to a bad place. She wasn't someone to admire, and all through the series the signs were there. For some reason, many people didn't see them, or chose not to. Dany going mad was something I assumed from season two, and I saw the signs. It was one thing the show did well, IMO.

Also, the show brought up her genetic heritage many times. In the last couple of eps, it was even addressed directly re: Jon compared to Dany. So even if you missed the signs, you had this narrative anvil going on.

Like I said, her descent plummeted the last few episodes, but that's pacing not plot, and don't get me started on pacing.