When you take a checkride at the end of training to earn your pilot certificate, it's not an FAA employee riding with you... it's a "DPE" or Designated Pilot Examiner, who is a private individual designated by the FAA to conduct check rides (and who often charges you a fee to administer the test).
Occasionally an FAA employee will ride along with the student pilot and DPE to evaluate how the DPE is evaluating prospective pilots.
It has to be a complete plan, not just a slap-dash "we can hire some people and the problem is solved".
To do it best you do NOT hire from the industry, and if necessary you hire from unrelated industries (perhaps, for example, oil rig/pipeline inspectors).
Deliberately sabotage the regulatory authorities, then use the fact that they no longer have the expertise and staff as a justification to outsource the regulation function over to the companies that were supposed to be inspected.
And when it goes wrong, which it always does, make shocked pikachu face and claim that nothing can be done because we no longer have the capacity to regulate industry.
This would be less infuriating if this was the first time, but it keeps happening again and again and people keep falling for it. It is immensely profitable for the few though, that might be why it keeps happening.
The fix is easy, just requires time and budget: rebuild that expertise and refuse to certify anything until you have the necessary capabilities.