The point of the question is to show how limited that information actually is. Just look at how small the Wikipedia article is.

No one is denying English people have set foot on Nicaragua. But to claim that’s what the joke is about is stupid.

No one is going to hear that joke and think “hahaha that’s a about a settlement in 1633! What an absolute reference! Classic”

If you asked about British/English colonialism it would take forever for the members of the public to reference Nicaragua.