I say “cowardly” because the opinion Roberts wrote betrays no hint that he changed his mind honestly. Instead, he simply asserted that the “penalty” explicitly so designated by Congress was, in fact, a “tax” — because if it were a penalty it would be unconstitutional, in his view. Therefore, it just wasn’t.
An honest revision would have required Roberts to come to a different conclusion based on a deeper understanding. Instead, he just cobbled together an argument that even he didn’t seem to believe in order to come to the result he wanted.
It was a result he sought because he wanted to “save the court.” But from what?