This is just my personal opinion, so feel free to correct me where im wrong.
Traditionally the entry level jobs in aviation where badly paid so even though training was expensive after a reasonable amount of time prospective pilots would jump to a legacy carrier where they could enjoy an upper middle class standard of living. In the old days a young student or a mature career changer could afford training without significant debt and later could hope for a reasonable pay and a cream of the crop job. The key over here was patience and determination. Now days cheap credit and the "I want it now" mentality lead many people to integrated schools with massive amount of debt hoping to achieve the job and the salary of the past. While low cost operators were hiring it was OK but now supply is well over demand. For example i read somewhere that in the US there are about 30.000 professional pilots flying for the legacies. So say that every year there is a need for 3.000 pilots,considering the amount of graduates from aviation colleges like ERAU and the military guys retiring, someone has to be extremely lucky to fly with the big players. I believe that the same, or worst, applies to Europe taking into account the lack of general aviation.Furthermore in Europe established carriers take their own cadets. In order for the T and Cs to be better there has to be a massive expansion or a much more limited supply. With the amount of people graduating from schools all over i doubt that there will be a limited supply in Europe anytime soon.
My personal view on this one is simple,
if the required hours for the CPL were for example 400 then it would be much more difficult for someone to earn his wings in an integrated school in a year or so.For someone in order to be a pilot would be a long time goal and determination would be needed. Furthermore earning all that hours would mean that more mature candidates would enter the profession. Generally speaking a mature person has more responsibilities in life and demands better T and Cs. Thats my thoughts on the matter.