XDash brings up an interesting observation that I think we often neglect here. A pilot that beats up the pattern for 1500 hours over 15 years is not gaining valuable airmanship experiences. A pilot that flies solid XC IFR for 1500 hours is going to be more prepared for a simulator and operating in Class A airspace. So here is the problem. It is impossible to put everyone into those two categories. There is a varying degree of experience and not many are going to have the same experience. I think we can all agree that a pilot with 200 hours of IFR XC will be far less prepared to fly an regional jet than a pilot with 1000 hours of the same.
I don't know that the current law fixed it. Since they raised the minimum to 1500/1200/1000/750, they have seen a sudden influx of hobbyist aviators. Joe FBO, who has been doing $100 Hamburgers on Sunday for 20 years has a midlife crisis and decides he wants to be an airline pilot. Instead of putting the onus on the regional airlines to ensure that they don't hire unqualified pilots, they see 1500 hours in a logbook and will bend over backwards to fill a seat. That is business being irresponsible. Now, they want to roll back the law because they didn't have any hiring discipline and don't want to wait 5-7 years from attracting a candidate until they can fill the seat.