I'm positive these students did use an LLM to get the help instead of crowdsourcing, but it is an interesting linguistic overlap.
And while I'm on my "old man" soapbox -- "look it up" and "search for it" somehow became "search it up" with the young people. I corrected my son for years before I started hearing college students also saying it that way...
It wouldn't actually be necessary for the phrase "look it up" to exist for this to happen. You're free to apply the particle "up" to pretty much any English verb if you want the semantics that it provides. Compare rustle up, turn up, etc.
You might also want to take note of the episode of Kim Possible where Ron is unsatisfied with the performance of an actor studying to play him, and tells the actor to "Ron it up".
I have been speaking English for 20 years but it's my second language. I don't think the semantics of "up" matters when I try to understand phrasal verbs like "turn up". I don't see anything about "up" (as in a direction) in "turn up" or "show up" when it means "to appear" or "to be discovered"... where is the semantic connection?? I think native English speakers just think "up" intrinsically relates to "appear" or "be found" but there's no such connection in other languages I know of.
Similarly with things like "fed up" (as in 'tired of'). Where is the "upness" here?
If I ask my partner to turn the volume "up," I am asking them to literally move the volume knob "upwards" towards the maximum limit. The physical motion doesn't literally track with televisions and remotes, for example, but you're still moving (turning) the volume upwards towards maximum.
That's how it shakes out in my head? You're moving something upwards towards the maximum. More is bigger, bigger is up.
In Chinese the past is "up" and the future is "down".
Having gotten that into my head, I now get annoyed by the hotkey controls for mpv, which use up arrows and page up to skip into the future and down arrows and page down to skip into the past.
First, regarding other languages, English gets this usage from its Germanic roots, and you still see that in languages like German, Dutch, Swedish, Danish, and Norwegian.
E.g. in German, words and phrases like "aufessen", "Iss deinen Teller auf", "austrinken", "Trink dein Glas aus". Dutch has "opeten" (eat up) and "opmaken" (use up). Swedish has "äta upp" (eat up) and "dricka upp" (drink up).
So really, English just inherited this and has had it for as long as English has existed.
In fact, the same seems to be true of Germanic languages - the widespread existence of this pattern suggests that it comes from proto-Germanic, the ancestor of Germanic languages spoken around 2000 years ago, or even from earlier Indo-European roots.
As for meaning, it's essentially a metaphorical use of "up" as meaning increasing, completing (fill up), appearing/emerging (come up), improving (touch up) - basically movement towards some completed or improved state which is metaphorically viewed as "up".
> Similarly with things like "fed up" (as in 'tired of'). Where is the "upness" here?
The upness is in having reached a maximum. An interesting comparison is "I've had it up to here!" which makes the metaphorical usage much more explicit.
They don't, but they matter a lot when you're coining a new phrasal verb!
(They still matter a little for verbs that already exist. You might see a verb mutate from using one particle to using a different one, but that would probably take hundreds of years.)