I think you're ultimately answering your question by bringing up Michael Corleone. His transformation from an emotionless and calculated war hero, to the need to protect his father and family, to killing Virgil to save his Dad which started a chain of falling dominos, to starting a new life in Sicily, to falling in love and getting married, only for his wife to be killed as revenge for Virgil's death, to coming back to America and more of his family dies, to eventually don of the Corleone Family at the end of is a gradual, well plotted transformation. Think of a diagnal line on a chart gradually going up.
Now think of Daenerys. If you take GoT as one large movie, for most of the story she is good. She is just. She is kind. She is the breaker of chains. Fair when she needs to be, as well as harsh when she needs to be. Sometimes emotional, but most often cool and deliberate. Marching to liberate the realms. Sure I guess there is something that can be taken as a seed there and there, but no seed is watered and the breaker of chains is still all the above, and suddenly BAM!!!!! She's annihilating thousands of innocent women and children for 15 minutes. Women and children. That's no diagnal line on a chart to me. That is a giant defibrillator spike on a heart monitor!
If you showed me some psychological strife along the way. Night terrors. Nightmares of murder. Talking to herself in shadows. Her acting not like herself. Hearing voices. Delusions. Seeing people she killed haunt her. Ghosts of her Father or Brother taunt her. Pepper that throughout the last few seasons. Not too much, but just enough. But nope.
So we didn't get Michael Corleone here to me. We got an Anakin Skywalker transformation. That's where I'm coming from.
However, to the people who are not bothered with it, I am happy for them and truly don't want to change their minds. I don't want to even change your mind truthfully. To be honest, I am even a bit jealous of it.