I wonder if there is really a shortage of engineers or if there is only a shortage of engineers willing to work for below market pay? From a market perspective

I wonder if there is really a shortage of engineers or if there is only a shortage of engineers willing to work for below market pay? From a market perspective, when there is truly a shortage of "X's" [science Phd's, teachers, engineers, etc] the price/salaries for "X's" go up.