In the specific case of mathematicians and physicists, I suspect there was some strategic consideration beyond merely market demand. The more mathematicians an

In the specific case of mathematicians and physicists, I suspect there was some strategic consideration beyond merely market demand. The more mathematicians and physicists you have, the fewer anybody else has. "Brain drain" can harm perceived competitors even if you don't necessarily have anything to do with your extra brains. In the more general case though, the STEM system is just designed to make it easier to get the people deemed more important, just like the Canadian system. The only way that they differ is that perhaps the Canadian system determines importance more accurately. I am sure the STEM system wasn't intentionally made worse, that's just the sort of thing that happens sometimes.