This plane is designed to be flown by inexperienced pilots, what if Germany was able to build he-162 in large quantity, would it help Germany take back the air superiority?
Flying itself is a very disciplined exercise; which requires hundreds of hours of training. And air-combat requires more strict training program than commercial/recreational.
As for new weapons, history taught us a weapon is only as good as the man who's using it. To make a new weapon effective on battle field requires new strategies and tactics. More importantly, to win a battle is one thing; to win a war is a different story.