While I agree with UBI at a philosophical level, attempting to study it scientifically with a sample size of N people in an existing functioning economy is pointless. If 10 people have UBI and 1000 others are doing regular work, you can't turn around and say "see how much happier the 10 people are!" Of course they are happy. They earn more money than their neighbors for doing less work. Now give everyone else the same amount of money and see how things play out. Is rent going to be the same? Is anyone going to be working menial jobs? Is UBI going to increase income inequality by sending more money to the capital class (like say COVID relief checks did)? We won't know all this until such an experiment is done at an economy-wide level.