Everyone overgeneralizes from extremely limited data. At least, I do.

I don't think it's a joke. You have no choice but to overgeneralize from experience. If you limited yourself to only what you can support by direct observation, you would be catatonic or dead.

Perhaps you have no choice but to generalize from experience. But some people are better than others at avoiding overgeneralization.

Anyway, the juxtaposition of "Everyone ... At least I do" seems to peg it as a joke, given the subject.

For example, I figured everyone would continue to write one-line responses, making this thread continue in its pleasing diagonal venture across the page. Guess I was wrong.