What did GA teach me to help being an airline pilot? (Could be a thread in its own). Do I wash aeroplanes now? No. Do I spend all day photocopying? No. Do I get put in the position of doing something that requires a very liberal interpretation of the rules daily? No. Am I being shafted by my employer whilst having to say thank you? Probably yes but you can’t win them all.
I agree that I had a ball in GA, but it had little to do with airline flying. If you can’t fly an aeroplane after 200 hrs then 5 years in GA won’t help.