Labor scarcity in the sense that there's not enough people who need work, or in the sense that there is not enough people who have the necessary skills? I would have to assume the latter. If that is the case, aren't most of these scarce skills the type which are used to service and maintain the very automation which would be used to implement a UBI?
>When robots provide the same level of services to the US middle class, that would be a signal that we might need to think about something like a BI.
Automation already provides a much higher level of services than human workers in many areas. Do we really want to wait to the very end of this process to begin the transition?