Another thing the article mentions is a 4400% increase in the number of jobs. This is not population growth, (it is only 3 generations assuming child labor), so where did those people come from? Were they more skilled workers earning good wages replaced by automation? Were they unskilled workers whose previous jobs had been automated away (ditch diggers and the like)?
In one case you have a net loss in liquidity in the hands of people, this is the net equivelant of lost jobs. In the other case you have a potential gain in liquidity. Once again, not making a case for or agains the automation, just discussing if the employment is equivelant.
To use your analogy its not like me asking if we should continue with the rugby at all. It's more like me saying "Hey guys, I know that the mechanism is different, but can we also look at the fact that 100 more teams in the cup might dilute the quality of play?"
Yes. There is an assumption that employment is better then unemployment, indirectly. The point being challenged (automation causes unemployment) assumes that unemployment is bad and the counterargument goes on assuming that. It doesn't (as you suggest) assume that employment is the only possibly important thing in the world.
If you would like to make the case that employment is not good or that automation is bad for some reason not related to employment, go ahead. It is perfectly reasonable to write that article with the assumptions that it made.