[bronco21016]

It was most definitely a huge change in practical terms. When regional airlines began their boom cycles they frequently lowered their minimum requirements to essentially only requiring a brand new commercial pilot certificate. In theory that could be as low as 275 hours or so. I know many people were hired in the 300-500 hour range.

Raising the bar to 1,500 hours drastically changed the hiring landscape and coupled with mass retirements due to the age 65 rule (retirement is required at age 65 for 121 airline pilots), the airlines have had to improve working conditions to continue attracting qualified candidates.

All you have to do is follow the money. The regional airline association of America lobbies extensively for lowering the bar again to save regional airlines money.