I just wanna see how much of a know it all I can be.

I think that the joke here is:

Internet polls (and most polls in general) are notoriously inaccurate. The people who make up polls aren't really a random sample. So by making a poll that asks the question "Do you participate in polls?" Mr. Bubbles is purposely making an inherently inaccurate poll. Only people who participate in polls will answer and the ones who answer 'no' are, for lack of a better word, liars.

I think thats the joke. Tell me if I'm wrong.