I hate how simplistically they're addressing ideas of morality in this show. Jon was willing to break his oath to the Night's Watch in earlier seasons. He killed Quorin Halfhand out of necessity. He broke his oath of celibacy with Ygritte. He said fukk it and left the Night's Watch after being betrayed.
I know it's being said over and over, but the writing has done a disservice to this show. I'm cool with how things have gone, but I hate how we've gotten here. Like, is Dany the Mad Queen now or is she just a Queen who got mad?
Insanity isn't what I saw in her actions. Missandei's last words weren't meaningless. Nothing up to this point has indicated Dany is mentally unfit. So either someone who has exhibited extreme patience and the ability to rationalize lost her mind in an instant, after already having won, or this breaker of chains who fights for the people and wants to break the wheel just threw away all of the convictions and ideals she's been shown to have for 7+ seasons merely for revenge. Neither of those choices is redeemable from a writing standpoint