I don't think it's going to be in any way easy to convince people that it's okay not to be useful. No matter how times we care to repeat it, people will still feel dejected and hollow. "What is the meaning of my life?" is a difficult enough question to answer when you're a philosopher who has studied the problem academically and you're surrounded by other people going about their productive lives and overcoming various challenges in order to survive.
Now we're supposed to have millions of people face the question and at the same time tell them "no, there's nothing useful for you to do, robots can already do it faster, cheaper, and more efficiently than you will ever manage." So, what? Do we tell everyone "just go smoke weed and play video games"? Or "go kayaking and hiking and rockclimbing and find yourself in nature"? The latter will not scale. Many natural places are already overcrowded and we don't even have a post-work economic system in place.
Now we're supposed to have millions of people face the question and at the same time tell them "no, there's nothing useful for you to do, robots can already do it faster, cheaper, and more efficiently than you will ever manage." So, what? Do we tell everyone "just go smoke weed and play video games"? Or "go kayaking and hiking and rockclimbing and find yourself in nature"? The latter will not scale. Many natural places are already overcrowded and we don't even have a post-work economic system in place.