Hum, do we really need to see this as white and black. Work or no-work? Why not just introduce 30 hours/week or even 25 hours/week. And by that I mean employees keep the same weekly salary, companies use the gain in productivity by automation to give back some family time to employees. What we get in exchange, is one or 2 extra days of consumer spending. People tend to spend more during weekends anyways, so everybody…
UBI I would argue is much more desirable, if you were going to try to legally force 20 hour work weeks. UBI actually lets you absolve a lot of historical regulation that holds industries and growth back, that was all established as an attempt to protect the poor and uneducated from exploitation. When everyone has an easily accessible minimum standard of living, regulations in the workplace can be retired to enable more innovation since the workers can finally negotiate evenly with the employer rather than being exploited to survive. It also lets those workers with the ethic to do so to spend as much time as they want making as much money as they want, knowing they won't starve or go homeless when they stop.
Either you keep cracking up the extreme regulatory machine currently asphyxiating the American corporate sphere (ever wonder why all the innovation is in software? It isn't just because its new, it is also because relative to almost everything else it is extremely unregulated) or you just use increased taxes on unfettered growth to provide for the masses so that the unleashed potential doesn't destroy lives.