I also get the feeling that such experiments just prove that giving people money makes them happier. But there’s nothing to account for the fact that prices in the market haven’t changed, the tax structure hasn’t changed, and no goods or services experienced any shortages.
I'm not aware of any realistic UBI tests. Could you point me to any?
The ones I'm aware of were either or both:
1. Time limited, so participants were aware that they needed to still have a job or at least be employable after the experiment has concluded.
2. Were funded externally, so participants only reaped the benefits of UBI but didn't incur the drawbacks (i.e. didn't have to fund the program by much higher income taxes) which could have discourage them from working.
It was basically a supplementary source of income - money for nothing for a limited time period, not an actual UBI program.