The problem, from a dramatic standpoint, is that to have a future celebrity you have to have to first invent some sort of future art or sport, which runs the risk of looking silly if you do it wrong. "Ohmigod, it's Swarara Ginsu, the worlds-famous bio-holo rap artist! I love her neo-retro-steampunk laser operas!"
Easier, especially in an hour-long episode, just to have a string quartet or a Shakespearean acting troupe.
Wait! I just remembered. Didn't B'Elanna like to read Klingon romance novels? Like Woman Warriors at the River of Blood