I think it all works, to be honest.
The movie has three core messages:
- Step outside your echo chamber and form your own opinions.
- Everyone’s a little bit racist, but that doesn’t make them an irredeemable bigot. Seriously, go listen to the song.
- Emotional arguments only work if the person is predisposed to agreeing with it. You change someone’s mind by appealing to their experiences and sensibilities.
At the start of the movie, Sunny has a romanticized view of unicorns and pegasi, based on her father’s research. When we flash forwards, we understand that Sunny has had to become more mature and independent as a result of Argyle’s passing. However, her view of unicorns and pegasi hasn’t evolved; it’s still shallow and superficial, and it’s still just her repeating things her father said. It’s worth noting that if Maretime Bay had extended the hoof of friendship, we can infer how that would have played out based on the standoff between the unicorns and pegasi in Bridlewood. A standoff that Sunny was only able to diffuse because of information she had gathered herself.
Sunny spends the second act having her own perception of unicorns and pegasi challenged. The Sunny that crashed the CanterLogic presentation isn’t the same Sunny that re-united the three tribes, and I think the movie just trusts the audience to understand how she grows from her journey.
Sunny being a little bit racist means that she isn’t “better” than anyone else. At the same time, the offensiveness goes completely over Izzy’s head. Her obliviousness to things that could offend her makes her happier overall, and helps her bond with Sunny. Most of the prejudice is based on misinformation rather than genuine malice.
Edit: Where I’m currently at is that Sunny had an arc, but the payoff is unconscious/unspoken. It’s entirely possible that the emperor has no clothes, though. I think this is the litmus test: the next time we see Sunny, is there an emphasis on her doing her own research rather than repeating things she’s heard?