Productivity and other arguments aside. I think we still need a fair bit of advancement before this is possible.
We need to reach a point where robots can maintain themselves and all of our complex machinery. The maintenance required for a train engine or train tracks is non trivial for example.
We need advancements in energy. Solar is not enough at it's current state but I have hope it soon will be.
I do feel, we're at a point that, if we could focus a lot of resources, we can drive enough development to give everyone a very high quality of life for free.
At this point,the machinery we make the more machinery we have to maintain. And robots are not at the point where they can do this.
I hear what you're saying, and I agree it is very optimistic.
But is it really? You can fit an RMV into a Redbox machine. You can fit a Dunkins into a machine the size of a 15 yard dumpster.
Then you don't need the train to transport all those employees to work.
What you actually want in society is for as many people as possible to have the means and motivation to contribute to social progress, to keep it as fair as possible. You want more independence, not more dependence.
In my head, universal basic income is more like tax returns, but each month instead of each year. Like a tax refund for food and shelter.
Hollywood has 10 years or relevance and 20 years of existence as we know it.
Ask your kids who Chris Pratt is. Now ask them who Jeris Johnson is.
You still need an army. If everyone stops working then our neighbors can just organize their guns together and steal our robots. Unless of course we had a fully autonomous military (techno dystopia "stop right there criminal scum"). But who oversees the military robots? Who oversees the UBI? Somebody has to do the dirty work, and those people will have power, and as we know, people who have power will ultimately abuse it.
Just because there is UBI and most people don't have to enslave themselves to eat doesn't mean people won't want to do something with their lives. Soldiers and officials get UBI plus salary and they are chosen the same way they are now.
It seems that you just want to setup a straw man argument that you can then knock down.
UBI doesn't replace all human labor. It just incentivizes automation and puts people first. You'll still be able to find a job as a mechanic or robot engineer or programmer if you want. Then you can take a paycheck and UBI. But it will be of your own accord instead of forcing you into compliance with wage slavery like we do now.
This is peak techbro arrogance. No, most jobs are not replaceable by code and "simple machines".
UBI by itself is basically a paycheck for doing what you love. Invent a new product. Make projects on github. Write a song. Be happy. Make other people happy.
The same people also conflate "capitalism" with "democracy" and forget that it is actually possible to have the latter without the former.
We conquered the world already. We have enough technology to replace most human labor with automation and enable people to produce entertainment, media, and innovation of their own accord. Instead people run around anxious and impoverished for basically no reason. You would never know humans are at the top of the food chain looking from the outside.
Why not get UBI done, replace the humans with robots, and then actually enjoy our lives?