For many years, the right seat was occupied by low time pilots. It was working just fine until Colgan. In the early '60s, United ran ads saying that if you had a private license and would go get your commercial and instrument, they would put you into their hiring program right now. A friend of mine had just gotten his commercial, instrument, and minimum multi time in an Apache through a USAF Aero Club, was hired immediately as a North Central FO in a Convair. He said the training kicked his ass as did some of the Captains he flew with. He retired as a very successful B747 Captain. So low time hires work just fine if the airline has demanding and high standards then. USAF lets their young new pilot trainees loose flying jets solo with less than 200 hrs. It’s the training program and the demands that make low time hire work. Also though, back when, the new low time FO was first flying a prop of some type. An additional 1000 hours as a C172 CFI hasn’t given that pilot any more real experience than he/she probably had at 500 hrs. As I said, low time FOs worked just fine for many years.