Let them have their fun. Related, some adults are watching The Matrix, a 26 year old movie, for the first time today.
For some proof that it's not some common idea, I was recently listening to a fairly technical interview with a top AI researcher, presenting the idea of the singularity in a very indirect way, never actually mentioning the word, as if he was the one that thought of it. I wanted to scream "Just say it!" halfway through. The ability to do that, without being laughed at, proves it's not some tired idea, for others.