The purpose of giving people money is that they have more money.
The fact it's even theoretically feasible is reason enough to pursue it.
What every UBI pilot proves is that the naysayers are full of shit. People don't drop out of society - certainly not over $10,000 a year, for maybe one year. Helping people buy food or dress nicer doesn't make their lives worse, somehow. Now: when people have a more significant and reliable increase in income, it predictably changes how they live, and often where they live. The impact would be drastically different if the sums were much larger.
But that impact is not the point. You have been robbed. We beat scarcity, and we're still cosplaying the past. Only a small portion of global society actually makes things and does stuff. The rest is either book-keeping, entertainment, or bullshit. By revenue - mostly bullshit. We could explicitly pay people to quit the jobs that are bullshit, and that wouldn't ruin society either.
In the absence of socialists enacting a plan besides 1. revolt into a dictatorship 2. oh no the dictatorship is bad actually 3. that doesn't count, UBI is the clearest approach to fixing all these stupid money-games. Is the economy running? Great, then everyone should have money. That's not gonna show up in petit studies for the same reason tidal waves don't show up in a glass of water.