Age, Habits, Hours and cultures
On the subject of experience and developing bad habits in GA. I tend to agree that GA is not the best overall place to obtainexperience for tghe airline world and that cadetships and ab initio styles are far better at tailoring pilots to produce outcomes. There are no real similarities in the equipment, safety cultures or operating environments between GA aircarft and heavy jets. Chalk and cheese.
As for experience and habits. I read on another recent thread all the attacks on the young and qantas FO who made input errors to the FMS in his 737NG and caused a terrain alert to sound on approach to Canberra. He was abused for being both "too young" and "too inexperienced" to be in the job by lots of pilots out there. Yet, right now over NSW there is probably a twenty year old flying solo in an FA-18 Hornet with less than 350 hours total time. Difference is, he is trained to do it, motivated and knows what his employer expects of him. Nobody says "boo" about him being too young or too inexperienced do they?
Quality of training, focus and motivation are what gets people over the line, the five years of bush bashing in a dilapidated old baron only make you a good baron pilot and really count for sweet FA in the heavy jet community. Take a look overseas, the proof is everywhere.