Have you ever closed your eyes during a movie or TV show and just
listened? I encourage you to give it a try sometime because you'll soon
'see' that the flashy graphics, bright colors, and fast motions are only
a small part of the art of storytelling.
One of the first things a voice actor learns as they begin their
training is just how hard it is! While a traditional actor can convey
emotions and intentions with movement a voice actor has to do all that
with their voice alone.
Casting the right voice is critical to the success of any media project.
If the talent can't convey the right intent, the story will suffer.
Here's two examples of how different a famous character would have been with some slight alterations: