Put Mario Andretti in a Yugo and he isn't going to win a race no matter how skilled he is.
Pretending "it's only the pilot" is a pretentious claim (one that serves to boost many an ego, IMO). It's not the plane either. It's how a pilot uses a plane. The plane amplifies the pilot (whatever his skill level may be).
Spits (in this game) amplify it a LOT, hence a lot of no-skill pilots get plenty of kills.
Put a pilot in a plane that stalls out when you bank 15 degrees, and another pilot in a plane that never stalls or spins, and I promise you it's not just the pilot skill that determines the fight.