I'm not sure how this observation defeats the purpose of economics. The reason you give people a basic job is not that we need the work done --- after all, the alternative to it is the basic income, which pays them to do nothing. The purpose of the basic job is to fix the incentive problem of a basic income, which would encourage people not to work because there'd be inadequate marginal benefit to a low-wage worker to take a job.
It actually pays them to do whatever they are doing. Living != Nothing.
There's no reason to imply that whatever the government tells them to do for their basic job produces more value than whatever they decide to do. It's pretty well established that the more government tells people what to do for work, the less an economy produces.
Lets make people pick trash instead of helping educate their kids, surely picking trash is of much more societal value...
The problem isn't that they're doing "nothing"; it's that there is a lot of work that gets done at the bottom end of the income spectrum that would stop getting done if a basic wage were provided. When people stop doing that work, the price of that labor increases, the price of the things that depended on that labor increase, demand decreases in response, more people lose their jobs, and people that depended on goods enabled by that labor --- people that include those people relying the basic income --- are worse off.
I'm pretty sure that printing money and giving it to poor people is a much better idea than printing money and giving it to rich people.
How come there's no basic job attached to the money GS gets? How come no one is worried that rich people are going to stop working after we spent 5 years giving them all the money we can borrow?
How many stockbrokers do you know that quit their jobs because the government is flooding the market with free money?
HSBC didn't stop laundering money for drug cartels just because the US gov't was offering them all the free money they would ever want.
That, and the fact that there are many jobs that could be done with some value. Picking up trash in a rarely visited park may not be worth $7.25/hour (presumably if it was, that job would already be being done in today's economy), but it might be worth $0.90/hour. Or maybe it's worth $2.34/hour or $7.23/hour.
I don't purport to know the answer which is why that number is a random variable.
