Pay Issues
The Pilot's Union is the US has surveyed and determined that the so called "pilot Shortage" is a complete myth. The issue is a shortage of pay.
The problem actually arose several years ago when the regional airlines were able to stave it off a while. The regionals simply lowered the entry qualifications so that many new hires were non the wiser to the effects of such low salaries. The 1500-2000 hour people were a bit older and had 4-5 more years of maturing to realize the consequences of such low salary.
Common in the US is a newly graduated pilot from a university program with 65,000 USD in debt. This guy will need to spend at least 10,000 USD more to get his CFI ratings, and then 4 years of time building to reach the 1500 hour ATP requirement. During the time building phase, they will usually get a job that pays more than their CFI job. By the time they get an offer from a regional, thay can be making twice as much as the salary they will be offered by a regional. They just can't afford it.
That 65,000 USD debt carries a monthly payment of around 1.200 USD. Staggering debt for such a low salary.
I teach in the mid-west, and the lowest time CFI has 1,200 hours. Almost all have over 2,000 total hours, and they are not applying.
This pilot shortage is still being trumped up.