I do not agree, silliness and quality are two very different things. Silly can be great. Look at Monty Python or Spinal Tap. Even Star Trek IV was silly, but it was a quality movie. V is just a mess, and it's not because it doesn't take itself seriously.
And that's even if I were to agree with the premise that it doesn't take itself seriously, which I think it does. I think they thought they were being deep with that whole "God" angle, and all that brainwashing people by removing their pain nonsense.