The idea being criticised is that - if a few humans dominate the economy by commanding huge armies of robot minions, then - without substantial taxation - the economy will grind to a halt - since hardly any humans are earning any money, and so therefore hardly any humans are spending any money.

The problem with that is that the huge armies of robot minions are consuming vast quantities of material while competing with each other for resources - and the purchase of all those goods is not being accounted for anywhere in the model - apparently because of the ideas that only humans are consumers and most humans are unemployed .

It seems like a fairly straightforwards modelling mistake to me. The purchase of robot fuel and supplies has GOT to be accounted for. Account for it as mega-spending by the human managing director if you really must - but account for it somewhere. As soon as you do that, the whole idea that increassed automation leads to financial meltdown vanishes like a mirage.

We already have a pretty clear idea about the effect of automation on the economy - from Japan and South Korea. The machines do a load of work, and their bodies need feeding - creating demand for raw materials and fuel - and the economy is boosted.