> If you create the jobs, people will change college majors or teach themselves. Industries will create apprenticeship programs to compensate for the undersupply, etc.
The dearth of plumbers, electricians, mechanics, welders, and other tradespeople in the US completely disagrees with this. These are very frequently high-paying jobs (even if you judge by the tech industry yardstick) and there simply aren't enough people to fill the jobs. Mike Rowe has been campaigning about this for years now, to try to get people back into the trade, and it's just not happening.