A friend of mine's younger sister had a friend who was named
Rio (female), and her (my friend's) mom thought it was just the most ridiculous name ever, she was always shaking her head over it. Possibly it felt more preposterous because the
Rio in question was apparently a bit of a rich spoiled brat type. I always thought the name was kinda cool, very hip and exotic.
I do think of the song, and also that movie about the parrots. It's firmly Spanish for me.
I think it could work for any gender, but on a boy it feels a bit more silly, like an adult film star type of name. It seems more cartoony on a boy, like calling a kid
Olé or
Toro or something.