Productivity is defined as output per unit labour. This means any profitable investment the firm makes will increase productivity (assuming the number of employees remains the same). If the minimum wage was indexed to productivity, then any such investment would increase labour costs.
Yes, so the only way to increase profits is to increase automation. A much better use of human brains then using them to flip burgers.
So automate away all the jobs? What are people supposed to do then?
The sewers have put all the nightsoil men out business, yet I say society is better for automated toilets.
It remains to be seen whether we will really have enough "creative" work for people to do.
Enjoy themselves.
Live humbly on UBI, grow vegetables in your yard and invent a better method of automation in your garage. If you succeed at the latter, who knows? To me the point of UBI+Automation is that we unlock the potential of more people following a muse without needing to spend too much time surviving.
Latte art and craft brewing.
Funnily enough, Australia employs more barristas than coal miners, but the coal mining sector gets more government subsidies than the latte industry.
Indexing doesn’t have to be 1:1; the goal is to ensure some of the productivity gains go to the workforce, but that can be done while still allowing improvements to be a net benefit to the company.