Not that sad woman on TV isn't compelling or anything, but she's just being dumb about things she does not know. We've all done it before, just not a lot of us got to do it on TV and get paid for it.

To call somebody a muppet is generally because they've said or done something a bit silly. It's usually meant in an affectionate way.

That's British slang for what you're doing / how you are acting / how you carry yourself on right now ... is muppet-like. Therefore, "you're a muppet."

Not that you look like a muppet, just that you were possibly engaging in activities that made it appear like you were a muppet.

But she does look like a muppet, that's why one of them almost cracked when she said it.