They do go into the rite of passage quest she is on and why it is important which is fairly personal IMO. Also I think you got a lot of personality form all of the ME1 characters if you took them with you and listened to them while walking around or in elevators. Also the quality of the voice actor determines a lot about info dump style characters because the emotions shown in those conversations about potentially touchy subjects gives you a good idea about the character
In a sense every character is a info dump, whether its about their culture or themselves they are just dumping info. You don't get along with your father? "insert info dump about how you are a genetic experiment" They are all info dumps, its the quality of the acting that makes it or breaks it.
One issue with the elevators is their rather limited nature. They're not guaranteed to trigger, often replaced by the auto-transit system, past the Citadel they're extremely rare (only on Noveria for ambient conversations), and in Tali's case, we get her at the tail end of the Citadel sequence. Now if we were talking DA:O ambient conversations, which trigger quite often, that would have been awesome.
It's certainly nice having ambient elevator conversations, but putting aside their rather limited nature, Tali shouldn't really have a personality for 15 second intervals, then become the Quarian Codex for long stretches of conversation. That's why I often make comparisons with regard to Wrex, since he also does a pretty good job of evoking Krogan culture, but tends to relate it directly to his own personal experiences/narrative.
Good point regarding the nature of info dumps. It doesn't inherently have to be related to a specific topic. Voice-acting does play a big part, but so does the script itself as well.