I haven't been in this ng for a while--real life interfering. But I remember there was a discussion about why people were speaking English from our time, and the consensus was, "it's a cartoon, and the audience speaks 20th century English".
If you want a "within continuity" explanation:
When Leela was examining Fry on the Probulator, it inserted a chip to allow him to understand the languages it was programmed with. For Terry, Leela, and the others who spoke English before it was implanted, the building is equipped with a machine that does the same thing at a distance.
Leela: "Fry, you have to be more careful. You're not in the 20th Century anymore. You don't know how things work here." Fry: "I'm not a little kid, Leela. I grew up in the city. These are my people. What up?" Neptunian: "Word." Fry: "See?"
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"Maybe, just once, someone will call me 'Sir' without adding, 'You're making a scene.'" -Homer Simpson
It's a guess. That's why the word 'theory' is in the subject line. But I thought it the most reasonable guess. It's not really funny, as such, except in the sense that everyone around Fry is speaking their own language, but he's not aware of it.
It could be funny if at some point it is removed, or damaged in some way, or reprogrammed.
The comment by Grosse:
pretty much hits it on the head. I should have thought of that context, having been a Trek fan since it aired new. "D'oh!"
I think the likely answer is that languages get frozen once you have TV, movies, and recordings. I've seen that mentioned in in several different sci-fi novels.
On the other hand, new technology by definition requires new terminology. Also, new terminology can sweep through high-speed communications channels faster than a raging forest fire can consume a forest. What Up? Word.
Da Bomb.
etc.
How much slower would they be accepted (if at all), without teenagers on the telephone, for instance?
--> Oh, don't know about *by*definition*... I can think of at least one case where new technology relies on *very* old terminology... [1]
[/ nit-picking]
--> But a forest fire is a far more equal-opportunity destroyer...
--> And the propagation of these terms is due to high-speed communication, how? Now, if you had said, "ping... input... sticky," I would have agreed.
--> Oh, my bad. You're including the telephone in modern communication. Sorry...
There's still the "mass media marketing" aspect. How much of the propagation of new, non-techie slang is due to records/movies... whose acceptance/popularity is, in turn, due to the *obscene* amounts of advertising money controlled by the few dominant "entertainment" corporations?
And, thus (bringing the whole conversation full circle) if we extrapolate the collapse of independent studios/record labels/publishers from today to 3000, we may wind up with one monopolistic, damn-near-omnipotent DisneyTurnerViacomWhomever... and, similarly, extrapolate the growth of the power of media advertising to control the minds of people worldwide, (since we already know that Hollywood successfully manipulates the jargon and accents of people around the world) it might not be much of a stretch to assume that language may be fairly standardized/stable.
Or, it could be a stretch... 1000 years is a long time...