When talking about this movie, people frequently bring up the fact that the message boils down to the fact that, in the end, it really does matter what you look like, and that the ugly guy won’t ever get the girl no matter how nice he is.
Well. Those people are wrong.
Think harder. There are three contenders for Esmeralda’s affections - Frollo, Quasimodo, and Phoebus. Frollo has zero affection for Esmeralda. No affection, no respect, no good feelings at all. All he feels is lust. And when he looks at her, all he sees are her faults (or what he believes are faults). He sees her a sexy gypsy who has spent her whole life in sin. And that causes him to feel lust. Because of this, he is incapable of seeing her good heart and truly decent soul. He sees a problem in need of fixing.
The audience wants Quasimodo to get the girl because he’s nice and she treats him well, and he deserves to catch a break for once in his life. And those things are all true. However. That line of thought essentially equates Esmeralda to his prize, to an object rather than a person. The problem with a Quasimodo-Esmeralda pairing is the exact opposite of Frollo. Frollo sees no good qualities in her, Quasimodo sees no bad qualities. He puts her on a pedestal and blinds himself to any mistakes she may make or flaws in her personality. He idolizes her in a way that is not healthy.
But Phoebus… Phoebus sits between the two: he sees her good, he sees her bad, and he can see the whole picture. He sees Esmeralda as she actually is - a person. She is not a sinful creature in need of reform and she is not a perfect specimen of humanity. Phoebus is the only one who can see that, and the only one who respects her as a person instead of a prize.
And that’s why the pretty guy gets the girl.
"Frollo saw Esmeralda as a demon. Quasimodo saw Esmeralda as an Angel. Phoebus saw her as Esmeralda. That is why Esmeralda fell in love with Phoebus."