Social safety nets today are needed weslth distribution. A UBI needs to cover everyone. With the same funding a UBI would have to provide less benefit than the programs we have today.
That said, my argument against a UBI isn't even that it's too expensive. Anyone claiming that a UBI will be too expensive is falling into the same trap those arguing for a UBI fall into. The impact when making such a massive change to our social and economic system is impossible to accurately model and predict. The OP author actually seems to agree with this by pointing out that a UBI program can't be tested. Oddly, though, the author's solution to that is to YOLO a UBI program into our entire country without being able to understand what the likely impacts will be.
UBI requires changes to the tax code, but look at the comparison between SNAP and the 10% tax bracket for people making 0-11,600$ in the US: https://news.ycombinator.com/item?id=41086690
At least for single people how SNAP sunsets with income is almost 1:1 with the discount for the lowest tax bracket.
Thus changing SNAP to a low UBI could have almost zero impact.
That said, my argument against a UBI isn't even that it's too expensive. Anyone claiming that a UBI will be too expensive is falling into the same trap those arguing for a UBI fall into. The impact when making such a massive change to our social and economic system is impossible to accurately model and predict. The OP author actually seems to agree with this by pointing out that a UBI program can't be tested. Oddly, though, the author's solution to that is to YOLO a UBI program into our entire country without being able to understand what the likely impacts will be.