What good is a grand new economy if there's nothing in it that I can see myself getting paid to do?
This is the basic problem. All these futurology pieces extrapolate the supply side: what will be available, possible or substituting existing stuff. But none of them take the next step of analysing the demand side: asking who will be the customers for these advances?
Even if we end up removing all the manual manufacturing, office-based administration, transport and food production jobs, who will be able to afford trips in flying cars, or would need an AI in their pocket?
Even if we do get a UBI economy, will that basic income contain provision for computerised meds, and why would people with no prospect of a job - or more importantly: the children of people who don't / can't / will never work in their lives - ever need high quality online education (or any education at all)?