Doing away with Monday certainly has a nice refrain to it with or without lasagne. I disagree on several points, though. I don’t think UBI is tied to the libertarian wagon whatever that fringe in silicon valley thinks. The libertarian place has no there, there. It just hangs around but never does anything. So I see UBI primarily as Livvy, in his response does, as a move to absolute guarantee for all in order to open the opportunity for creativity, community service, gig type employment, or recreation. Because UBI must be a minimum living wage it needs to be tied to full, governmental service including full health care and free education for 14 years. This provides cost savings to businesses and could provide another day off to workers. Because I see AI replacing more like 40% of the present workforce in ten years I think a lot will self correct.
The other fundamental change will be in capital redistribution to do this. It just work, as I think you are saying, just by eliminating welfare, waste, and reducing public expense. It will need to happen by a full economic restructuring that pays everyone on the basis of asset ownership. This is much more difficult but will result from the general failure of neoliberal, hypercapitalisn. It will be very painful and this will be much harder than people think but it will also, potentially, self correct.
The real problem is people thinking that this will be just an adjustment to correct for Trump. Trump is the beginning of the collapse. We need to get very active with this conversation while blocking as much damage as possible from the Trump disaster. Making it will depend on a staged move to a sustainable, planetary economy.