Intentional joke in Haus of Holbein?

After having the soundtrack on repeat after seing it live last night, I think I caught a joke that I'm not was intentional or not. Is "wunderbar" a play on Wonderbra? Would make sense in this context. And yes, I know what wunderbar means. Thoughts?

"We must make sure the princesses look great When it comes for a Holbein portrait We know what all the best inventions are To hold everything up Ja, it's wunderbar"