All of this is premised on the very questionable notions that:

1: Work will fade away and automation will provide plenty. The alternative view is that machinery will displace people, much as steam looms replaced had weavers, or railway trains drovers and carters - and we will find new things to do. That leaves a residuum of people who cannot or will not up-skill, which reduces to an issue of welfare.

2: That the nation state will hold up as the unit of solidarity. Denmark looks after Denmark's deadbeats. That model may fail in the next few decades, for lots of reasons. We have acquired the habit of assuming that the able will support the less able, region by region, each treated separately. The capable accept that the state lifts half of their earnings from their pockets for nebulous schemes of general welfare. Patience with this may fade as the unemployable cease to be relevant at any level. Note, too, that a UBI without boundaries will dissolve into the poor billions, leaving nothing to the incapable in the rich world.

3: Demographics mean that support for old age will consume a third or mnore of state spending in the old rich world, and continue to do so into the 2040s, even is life extension technologies do not expand on that.

4: The much more likely world is one in which intellect-multipliers are focused around corporations and innovative/ wealth generating clusters, amplifying their abilities. This is not either machines or people, but machines with people making something truly unimaginable from contemporary perspectives. Plug that into (2) above and you get something strange, a "business class" world interlaced with assorted blocks that have been left behind, are racing to catch up, are physically co-located with these centres of excellence or geographically remote from them. The politics of that are unimaginable, but the won't be majoritarian democracies in the C18th of the US, Europe and so on.

This whole boondoggle rests on an extrapolation of the post-WWII consensus into infinity. What any futurist should be looking for is trend breaks. The adult welfare state, however modelled, is trend-broken, but it just hasn't recognised this yet. Still less has it begun a debate about what the new dispensation should look like. But UBI, with its innate nationalism, its retrospective model and its economic assininity is not that model.