Christoph Waltz, best known as "the Jew Hunter" in Inglourious Basterds, is perhaps not the first person who comes to mind when you think of grown-ups who love Sesame Street. There's quite some dissonance between the serious Austrian actor and sunny days and/or everything being A-OK. So you'd be surprised how chipper his version of the show's classic theme song is.
Kidding! It's bleak, severe, and drenched in despair, just like you expected. Have a good day, friendly neighbors.