Goku has Japanese traits, not America traits.
Bulma's hair is blue, not brown with a streak of blue.
Roshi is bald and has a beard, he doesn't have grey hair and is clean shaven.
etc etc.
They need to do some research. Chow claims to be a Dragonball fan, but I doubt it.
nb4 BAW YOU EXPECT TOO MUCH.
I don't expect much, but I expect them to do things right.