Game of Thrones, the show based on the Song of Ice and Fire novels, is a bit more about putting spectacle over story. But Queen Daenerys as the final villain, rather than Cersei or the Night King, is George R. R. Martin's surprise ending, make no mistake about it. Viewers were naturally horrified to watch a sympathetic character turn bad, but that's the whole point! We were tricked in order to get us to understand the cruelty and horror of war by watching a character we knew and maybe liked become a tyrant.
This isn't just my hot take on it, either. George R. R. Martin was a conscientious objector to the Vietnam War. He acknowledges that the perception of war as something glorious is a problem. Though not a radical pacifist, he states in this interesting clip that his goal with A Song of Ice and Fire, is to show the true cost of war.
Violence under the guise of "breaking the wheel," promoting democracy, human rights, and most other justifications is still abominable. That is why we should be looking for non-violent solutions to problems rather than perpetually glorifying war and violent conflict.