the UT is just a plot device. yes, they tried to "explain" it in ENTERPRISE (just one more thing that show was burdened with; "explaining" the handy plot devices the writers used to get through script and production issues. the "invention" of transporters as a way to get someone a great distance came about AFTER the TPTB's original idea-landing the enterprise every time-was seen as too time consuming, and the 2nd idea-using the shuttles didn't work because the models were not built yet. so "voila" "presto magico-el transporto!"
IT WAS NOT inspired by or backed up by ANY science--only the economics of a show's production:
"According to
The Making of Star Trek,
Star Trek creator
Gene Roddenberry's original plan did not include transporters, instead calling for characters to land the starship itself. However, this would have required unfeasible and unaffordable sets and model filming, as well as episode running time spent while landing, taking off, etc. The shuttlecraft was the next idea, but when filming began, the full-sized shooting model was not ready. Transporters were devised as a less expensive alternative, achieved by a simple
fade-out/fade-in of the subject.
[1]"
from wikipedia
the universal translator was a similar "convenience"
Clearly, Roddenberry and/or others could not let stand the notion of having humans and aliens communicating WITHOUT having learned the language(s) or had some translator
having an onboard person to trans for every planet encountered was anti thetical to the whole "explore new worlds" idea
and just having it go unexplained was not something the TPTBs could just let happen
so again-the UT was a prop of convenience-one we see "explained" by Hoshi in ENTERPRISE as a device that "learned" new languages' vocabulary,pronunciation,syntax,etc
but they never truly explained how it did that with languages the computer had no knowledge of in ref to newly encountered races
the same thing happens in many shows where it is just left alone. everyone understands one another and we are just to allow that every alien in the galaxy understands/speaks English with an American dialect!
SG1/SGA did this. they never explained it at all, though a small effort to kind of retcon the english as the off world lingo for the galaxy was attempted. In MOEBIOUS-when they went back in time to ancient Egypt-I dont remember who it was-(Daniel?) was teaching the ancient egyptians english
therefore, they and all others who followed in abduction off world, learned and spoke english
presumably, they also taught the various earth ppls-widely spread, chinese, mongols, celts,etc-english as well--somehow
that is why that "explanation" doesn't work--but I drift