I'll also tell you why I consider it the least of the parts. Giorno himself isn't cool. I know that's immature, but if a main character is constantly shown to be not as good a character as a supporting one, then that MC fails. Giorno wasn't just inferior to the likes of the rest of the gang (ESPECIALLY BRUNO HOLY SHIT WHY WASN'T HE THE MC), he had absolutely no personality. You wanna know what his personality is? "I, Giorno Giovanna, have a dream." That's literally all I could tell you about him. Less character development than Santana.
And don't even get me started on the ending. Every other Jojo was able to use their own skills to beat the bad guy. No kind of bullshit had to be pulled from nowhere. So because Diavolo, a terrible antagonist already, was too OP to defeat regularly, GER had to be pulled from literally nowhere. At least when Killer Queen got a weird new power, it made some sense to the character and had drawbacks. It's a classic case of being written into a corner.

Hey now, you animators you. Let's get the best part out of the way before we start giving hunts at the worst.