Flight Safety First - Cost Last.
Yes business operates for profit. Airlines run very costly businesses. So to improve the bottom line do you:
1) Cut wages,
2) Reduces levels of maintenance,
3) Push flight crews to fly longer hours at less pay.
4) All of the above.
Most airlines do all of the above and more. Bringing in new rules to reduce human oversight of flight operations is not safe. Why change the system? Why should aircraft be able to join on base. You need oversight by radar to control aircraft in a safe manor. Having aircraft fly a pattern before landing enables approach/tower to better control flights. It allows for safe spacing of differing types of aircraft, rather than a cessna 152 and boeing 737-800 fighting it out at the point of joining base.
There should always be separation of light aircraft from the heavy. Having an 'open skies' policy and leaving it up to the pilots is not safe.
The flying public should know that below 10,000ft under this new system it's every pilot for him/her self. It is a cloudy day, with cloud bases around 7,000 your decending at 250kts through fl07 in a 737 and out pops a c152 at 1 mile. No TCAS warning, no radar control for separation, and no requirement for the c152 to call to advise he/she is entering that area, is that safe?