The joke is more likely to resonate with the audience if it corresponds to their experience.
If they laugh, that proves I'm right;
Note the difference in meaning between the two italicized phrases?
Consider "proves" replaced by "is evidence in favour of". It doesn't change my point.
if they boo, that proves I'm right.
What did I say that could reasonably be interpreted this way?
That's the other half of the pattern -- which you obligingly go on to complete:
Laughter is evidence that you're right, an extreme negative reaction is weaker evidence that you're onto something.
That's the other half of the pattern -- which you obligingly go on to complete:
Laughter is evidence that you're right, an extreme negative reaction is weaker evidence that you're onto something.
Did you read the sentence I wrote after that one?
Indifference, or a non-extreme negative reaction is thus evidence that you're wrong.
As Multiheaded added, "Personal is Political" stuff like gender relations, etc also may belong here.