So I think I realized my main issue with Dany doing what she did and the army following.
Not that it made zero sense or that it came out of nowhere, but that it served one specific function.
To shock the audience. It was a decision made for the impact it would have on us, as opposed to simply being the logical part of the story. It's the intentionallity, or at least what feels like the intentionallity.
With stuff like The Red Wedding, that felt like where the story was going and the shock factor was a very pleasant perk of that. But Dany and the armies killing everyone felt, first and foremost, like a way of impacting the audience.
Not sure if that makes sense.
And obviously we'll never really know for sure. But that's my interpretation and why I think I have such a distaste for it.
I saw this post at the time but didn't really think there was much to say in reply, since I understand very much the point you make and how someone could see it that way, and while I don't fully agree I felt that to say anything counter to it would risk seeming like trying to invalidate your perspective on it. And that's not at all what I'd want to do - the issue you described is pretty much something that people either feel or don't feel about certain scenes and describing reasons why it comes across one way or the other can't change someone's impression from it.
But, since I see you mentioned it again to see if anyone has any comments on it: I definitely know the feeling you mean, often when I dislike writing it's because I feel like I'm seeing through to the writer's intent to force a certain reaction. I think that poor writing can take you out of the story and make you focus on the way the writer is trying to achieve something, in a way that feels manipulative or shallow. And I think if someone feels that way watching or reading something there's little that can stop them.
However, arguably any scene could potentially come across that way, since good dramatic scenes are by their nature trying to achieve a certain function. The Red Wedding was trying to be shocking too. Obviously for most people it worked and they didn't feel distaste at seeing an attempt by the writers to shock them. You described it as feeling like a more logical progression of the story making it feel less like a transparent attempt to impact the
audience, and I agree, but I could see how someone could feel differently and if they did I don't know that there's something to say to "convince" them otherwise.
So with that in mind, in the case of King's Landing, I felt it was somewhere in the middle - not quite as elegant and logical as the Red Wedding to keep me in the moment or make the shock tactics feel quite as earned, but not enough that it felt like "just" going for shock value. I've posted earlier about one of the ways the decision was built up to and emerged from Daenerys' viewpoint, I think there's a lot more you could say about it as well, so for me at least there's definitely enough there to dismiss the idea that it was completely forced. But, I think it is clearly such an extreme course of action that it makes sense to think "Why the fuck are you doing that?!" - and I actually think that's a
good thing, or at least that it's an intentional possibility of the story we've got. Discussing or thinking about why Daenerys would burn King's Landing, wondering if the signs were really always there or how she felt it as justified in the moment or if she just went batshit insane, I think it's probably the most interesting topic from the season (at a point in the show where there aren't as many hidden agendas or motivations as before like you said). And for me, looking back at past scenes and analysis certainly helped sway me further towards the side of interesting but logical progression of the story rather than a decision primarily forced for the shock. I'm not saying anyone else has to consider those things or that it'll change how the scene came across, but if nothing else it's interesting to consider the extent it makes sense or not.
Also (since I may as well load up on the possibly controversial points)... I think that something like whether you see something as part of the story or you instead see the authorial intent laid bare does depend on the mindset of the person watching. And I think that's something that'a true of a lot of things - someone said earlier that you can't just choose to enjoy or hate something, and that's true to a certain extent but I think it's bogus that you can't somewhat choose the attitude you approach something with. Put it this way, if I sat down to watch season 8 with the intent to find loads of examples of Dumber and Dipshit's Bad Writing
TM, I could do it. Instead I approached it with moderate expectations, hoped to make the most out of what we got and tried to remember this was the end of a great show that I'd enjoyed for a long time, and I'll probably appreciate the whole story more looking back if I try to enjoy what I can of the ending now when watching it for the first time rather than dwelling on inevitable disappointments about things left out, things done differently, things done poorly. Some people might see it as willfully ignoring flaws or forcing yourself to like something but I certainly don't see it that way.
Similarly when it comes to scenes and the intent of shock value, I could sit down and watch the Red Wedding with the attitude of "Ok, they're obviously trying to shock me with this massacre". The way it begins with stabbing a pregnant woman in the belly was clearly aiming for shock value rather than because it's the most logical way - and I can even say "THAT'S NOT IN THE BOOKS!" so they clearly deliberately added that to impact the audience. They even leverage the other typical cheap emotional death, a dog dying, even going out of their way to raise hopes Arya might release the direwolf just to surprise the audience when he dies (even though it doesn't make sense for Arya to be able to sneak in to near the direwolf).
Now I'm not sure why I'd want to take such an attitude since I don't think it would enrich my life much, but it's possible. Obviously I don't think most people deliberately decide whether to view a scene one way or the other, mostly it's just a matter of whether the writing works for you or not. But I definitely think viewer attitude can give things at least a little nudge.