Bono's talking about the verse melody of Best Thing, not the chorus or any other part of the song. I agree with him, U2 are known for their big melodies and TJT tour reminded them of that. The chorus of Best Thing is mainstream sugar and too sweet for my tastes, but I really love the melody of the verses.
"Just play another chord if you feel you're getting bored." Maybe Edge needs to write songs like Best Thing so we can get the more innovative, atmospheric tunes.