Are you saying that trucks are obsolete and truck drivers are no longer needed in the US? Horses and buggies are obsolete so that is why there is no great demand for buggy drivers. (Actually, they’re called ‘Teamsters’)
What I am saying is that if the efficiency of a product, in this case horse and buggy drivers or milkmen, is no longer efficient in the market process, then it should be discontinued. While this is yet to be seen in the American.\/Mexincan trucker market, it is a factor that must be considered into it