> but there is a distinct lack of qualified individuals to back that up
Which means either the compensation is insufficient to attract and retain the necessary number of qualified individuals, or the FAA lacks the resources to train an appropriate number of qualified individuals. Either way, it's about money.
Who would want to work that job once they find out what the day-to-day is like? I had an intern who looked at that out of the Air Force but he found out what you get paid and what the expectations are for the job and he figured he'd try his luck on something easier and better-paying like life-preserving medical devices. On a related note, why do you think nobody who you'd actually want teaching public school actually teaches public school in the US?