We already have case studies of heirs who have led/are leading happy and fulfilling lives without ever having participated as laborers in the economy. So it is

We already have case studies of heirs who have led/are leading happy and fulfilling lives without ever having participated as laborers in the economy. So it is proven that the combination of (having money and not having a job) is compatible with happiness. The misery seems to come not from curbing worst-case outcomes for everyone in society (by UBI), but from the threat of material insufficiency due to structural unemployment (which motivates UBI). Besides, even if we get strong AI and abundant energy to obsolete the vast majority of jobs, presumably it will take a long time to eliminate the long tail. One may always hope the next great genius/virtuoso will be among one's offspring.