Dude, it's RWJ... What do you expect?
It's not called 'stereotypes song' for nothing, obviously he's simply stereotyping. You should laugh at it, not be offended by it. He knows they are stereotypes, and stereotyping usually means that they are rumors which most people believe but are usually different. If he called it 'nationalities song', it would be different, but 'stereotypes' already shows he doesn't mean anything of it personally.
All these people overreacting are seriously annoying me. Don't watch if you don't want to hear.
I'd personally have loved to have seen a dutch stereotype in there, but sadly no.