Music Virtuoso? Cure Cancer? Ha! We'd be surfing the internet or watching TV. Possibly both.
Or, if you want to get away from screens altogether, which is what the question is really about, we'd be enjoying more traditional forms of entertainment, like reading, drinking in bars, debating, praying, and laying on the ground. Arguably, some people would produce some kind of art, though I'm not really sure why musical skill is being brought forward as superior to video gaming skill. And then, of course, there are the various non-video games, like poker, D&D, board games, and running down a street poking a ring with a stick.
Anything that costs a lot of time and money is likely to be beyond the reach of most people anyway. The training and knowledge to cure cancer is expensive and I doubt abolishing gaming would change that, with the same going for any advanced skill.