There's two points that I look at when I think of how much the Star Trek future is driven by people just doing what they enjoy.
The first is when Captain Jellico takes over the Enterprise and everyone gets all grumpy and Riker gets relieved of duty. Things aren't going well and Jellico goes to Riker's quarters to talk, and after asking for permission to speak freely, Riker tells him "You've taken all the joy out of everything." In this ship of hundreds of hyperqualified people working with bleeding edge technology, literally hours away from possibly facing their deaths and the start of a galactic war, Riker is correctly pointing out the the commanding officer isn't letting them have fun anymore. People in Star Trek don't get paid, they do what they do for the love of the game.
The second point is when Eddington goes rogue and Sisko realizes that he was fan of Les Miserables, and that Eddington is essentially cosplaying as Jean Valjean and wants Sisko to be Javert. Sisko points out that Eddington didn't have to become a terrorist or betray his uniform. He could have resigned any time he wanted. But he loved his role play so damn much that he was willing, even eager, to get the most determined man in the quadrant pissed off enough to hunt him down at all costs, and Sisko was able to use the implied script of this role play to capture Eddington. In this case, Eddington was having so much fun with his version of living his best life, he was literally willing to get captured and sent to prison because it was how he wanted to play the game.
People in Star Trek can choose to stay on any number of paradise planets, and quite a lot do, but they will also will face death and worse than death, all in the name of self-actualization, and that's pretty fantastic.
