The issues been studied in the U.S. Guys with flight training instruction, which is the overwhelming majority of new hires at the regionals, do better in initial training than guys doing jobs with little supervision like banner towing, glider towing, and pipe line flying. Every person knows of exceptions.
Does anyone think you're a worse pilot if you've flown more? Age becomes a factor at some point, I'd say around 50-60, but most people gain some knowledge and experience with longevity. But a factor in long haul flying is fewer flights, That can be an issue vs the n/b pilots doing more legs on one trip than some w/b pilots do all year.
You don't need a college degree to get an airline job in the U.S. It was a very low probability path in the past but the current system has plenty of opportunity, but still a minority opportunity path, for non college degreed candidates.
Europe doesn't have the GA/light aircraft training and flying system the U.S. has. I'd be surprised to see it change to a U.S. style training system.