That's nonsense. There are infinite possible jokes.

And memory is limited. What if one were a forgetful god. What if that is _already_ the case?

Possibly where the Alzheimer's patients are told the same joke over and over, and it does bring them joy, comes to mind.

This is not true. Jokes that take more than (say) an hour to tell are boring and thus not really jokes.

Literally there are about the same number of atoms in the universe as the number of shuffles in a 52 card deck (52!). The number of topics that can be played with in a joke is beyond even this limited number.

Remember, jokes about tinder/grinder dates didn’t even exist a decade ago.