Your hypothesis is that there are qualified welders, programmers, engineers, pilots, etc. out there but that no one is willing to pay the right price in order to get them to work for them.
As opposed to a hypothesis that too many people in this country are unqualified for the jobs that are open.
People will get the training for jobs that make it worth their while.
Increasing wages begat increasing supply of skilled labor. It also causes a shift of labor. My guess there are a glut of welders in South Dakota right now. But maybe there is a shortage of welders in Texas. If wages rise in Texas for welders they will come.