Why? Why would we want to invest a lot in a sector which pays lower than average wages? This would just be making us all poorer, obviously. Think on it: Fast food workers make less than accountants, so therefore we must invest in burger joints not financial management? No, of course not, we want to invest in the industries that pay the higher incomes to the workers, on the sensible grounds that we think it a good idea that people get higher incomes. Investing in manufacturing, given those lower wages, thus makes us all poorer — both by gaining more lower-wage jobs and also by losing the higher incomes that would have been gained by more sensible policies.
By the way, the very complaint being made of free-market economics is that it’s already doing this, investing in the better-paid sectors. That’s why there’s a plan, to force the market to stop investing in nice highly paid service jobs and to spray money at impoverishing manufacturing ones. The basic insistence here is that laissez faire economics is by itself and on its own making us richer. By golly, surely this must be stopped!