>"Yes, of course giving people money makes their lives better. It especially works when a very small subset of the population receives such treatment, such that their relative income is higher than those outside the experiment."

I've never seen a UBI experiment which demands that the participants pay more in taxes and forfeit all other welfare benefits in exchange for the payment. Every "experiment" so far has been measuring the happiness impact of the upsides without any of the downsides that would be necessary to make the program work.