Nero was essentially forced into puppet rulership by his psychopathic mother and then pulled the Uno reverse and whacked her before she could whack him. He was intrigued into the purple as a child through plots and murders with no choice or agency of his own, and ended up being the most hated and reviled man in the world when he was still a confused prepubescent idiot, and he still managed to turn it around and run that shit anyway, on his own terms. He did do some (many) horrific things, but most of his reputation comes from the fact that a bunch of retarded pissy senators and kingmakers kept putting inbred children in the purple and then throwing retard fits and trying to murder them the second a vote didn't go their way, and they spent generations still seething that Nero outplayed them.