the joke is that plan 9’s not UNIX, and thus does not run Jurassic Park. the absurdity arises from the fact that using such a capable operating system for dinosaur husbandry (im told this is what jurassic park is about) would be, frankly, philistine in nature.
So, falsehoods are jokes now? Hey guess what? I wrote xscreensaver! Haha, funny joke, right, philistine? Hilarious!
https://en.wikipedia.org/wiki/Philistinism