Sure it does, such a joke is often called absurdist or surrealist humor. Quite popular on Twitter.

Anyway, I think that is a lot more likely than some obscure cultural reference that we’re expected to parse in the middle of musing about digital mapping.

No, it’s clearly a joke - it made me laugh! It doesn’t need another reference point because the claim’s very existence is a reference to people’s reticence to admit their own age (due to vanity) or fear (of facing one’s mortality). That has been a common point of humor for ages (pun also intended).

As bizarre as this may sound to your generation there are, in fact, such things as standalone jokes.

I honestly don’t even know what generation you’re assuming I’m from and referring to. Is this supposed to be something old people don’t understand? Or young people?

Of course you can have standalone jokes, but “I’m six years old” is not one.

It’s not a generation thing. The joke is the OP is obviously not six. We know that because most six year olds can’t come up with such an artifact to set the timeframe of an article. For more references on jokes like this read MAD. ;)

Could you give an example? Even puns stand on aspects of language to acquire their potency.