The only good argument for UBI is: if we ARE going to have a welfare state one way or another, rather than funding a massive bureaucracy to decide (often arbitrarily) who receives “entitlements” and legislators wasting time trying to legislate what those entitlements are, better to just divvy it all up equally and give flat checks to everyone, to spend as each individual sees fit.
But therein lies the problem: the massive bureaucracy is self-sustaining and self-protecting, and will not go quietly in lieu of UBI. It will morph with a vengeance into a new layer of influence, motivated to identify & service those for whom UBI will be insufficient (either in totality or because many recipients will just waste it and demand more), restoring the same massive bureaucracy just shifted up one expensive layer.
Yes. The bureaucracy will need to remain so they can assure that some universal basic incomes are more basic than others...