Preferably, part of what makes the perfect Pixar protagonist is the protagonist’s characteristics and attitudes towards other characters. In other words, how they relate to the audience and overcome issues that a specific audience would have, Eg: In Soul, 22’s problem of feeling worthless could relate to those encountering a hard time and they too feel as if they are worthless. In Up, you get a grumpy old man, Carl, who finds his sweet spot after losing Ellie.
A major thing for the protagonist to do is to motivate or inspire the audience to feel better about themselves, or do what they love, be unique.
The protagonists have deep and difficult problems in which interfere with their own lives. It’s hard, it’s emotional, it’s infuriating, again it relates to the audience, but the protagonist is able to overcome the problem.
What also makes the perfect protagonist is the supporting characters. The best supporting characters are clumsy, funny, definitely unique, but most importantly, they are what help shape the protagonist and are just as important.
Idk hoped that helped. 🤷♂️