Anecdotally from my own experience I don't think there's a direct correlation between the younger crew force and mishaps. But there is something just as bad as mishaps the AF doesn't track and can't quantify- mission success or failure. I see young guys all the time making poor choices resulting in failure, but the plane lands safely so it's never more than a brief discussion. But mission fail at the tactical level over and over does have strategic ramifications.
For example, I see guys not being aggressive enough or not knowing how to be assertive during the limited opportunities we have to action objectives. I see guys weather cancel all the time when truthfully, the mission could still be safely accomplished. I see guys who can't do their fragged mission for some reason (WX, MX...etc) who outright cancel instead of looking around the AO, talking to the user and seeing what could be salvaged from the day. These are general examples. The truth is there are terrorists walking around right now who survived our strikes because we sent guys too young and inexperienced into the most challenging tactical situations with inadequate preparation. Or we sent guys who never should have been upgraded but were anyway to continue feeding the machine.
Bottom line, I don't see young guys crashing planes. I see them being timid. I see them unable to accomplish missions where the script isn't followed precisely. And what's worse- I see many of them continue on with successful careers after shaming themselves with incompetence in combat. I think the biggest problem with our Air Force is the inability to tie combat success/failure to career success/failure; were that issue fixed most others would resolve themselves.