It's hard to make the case that seeing a collision and not getting damaged is better for gameplay especially while watching someone collide with you, shoot you from the inside of your plane, and then fly away like some kind of ghost ship. It is just the opposite of both planes take damage if one person sees the collision. The best fix, though a compromise, is what we have now.
I can't see what is wrong with the way it is. You hit him, or your pc sees him hit you (same thing), you take damage. If you don't hit him, but he hits you, you don't, he does. Sounds pretty fair to me. Not sure how you could make it any better. Until we get insta information transfers that is:noid