Sure there could be a translation program, but that still doesn't change the fact that it is just damn stupid to rely entirely on technology in order to communicate. IMO you would need to have some sort of a backup in case for some reason that stuff failed. You're not going to wanting to try to fix you're tech while you're all speaking a different language. Hell, we don't even know for a fact that all of the human characters are speaking the same language. For all we know, Picard could be speaking French, Worf Russian, Choudhury one of the Indian languages, and Tryss could be speaking Mandarin.
Or since they have the UT they could start to learn it once they have started interacting with them more regularly.
Yeah, but they obviously knew of and had interacted with the Federation before. And if you are going to interact with someone you tend to learn their language first.Bajor was on the fringes of charted space at DS9's beginning - according to the show.
Or since they have the UT they could start to learn it once they have started interacting with them more regularly.