I am skeptical that UBI will work because paying people for nothing seems like it may be counterproductive by creating rampant inflation or by acting as a disincentive for most.
The rampant inflation argument, which most economists would use to argue against UBI, is interesting because most countries seem to be suffering from deflation. If deflation is a problem, then inflation created by UBI could be beneficial to an economy. But getting a government to start up a new UBI program to combat deflation does not seem like an efficient path for creating a solution because governments are slow, rarely do things correctly, and magnify their mistakes by taking years to correct initial imperfections.
Rather, focusing the brains, money, and technology of Silicon Valley on proving the idea with a cryptocurrency based UBI seems like a much more efficient approach to either 1) create a solution (the preferred option) or 2) settle the debate so that we can move on.