Like educating people on vaccines and masks, there are places where the willing population wouldn't be enough to draw from (ACK). On top of the amount of people sifted through to get a a few hundred eligible for the academy, the process itself to find a single person from a local population that is willing/able to certify would be a massive waste of money versus the ease that they have with it now.
Getting the FAA to sink money into something like that would be impossible. Better initial placement is needed, but hiring from local areas wouldn't be possible by itself.