I agree. Due to biomechanics and the build of everyperson being so different there can truely be no one perfect swing.
a look at the pga tour is a great example, everyone has different swings but impact is almost or identically the same.
its not whats right for everyone else its whats right for that person. The whole goal of teaching somebody for competition is to find what makes them hit the ball more consistent and if theyre lucky further. and also something that many people dont realize which i believe is that you will not use the same swing your whole life. it will constantly change whether its just a little nuance or a major change. Your body grows and changes, and many people even alot of the pros develop health problems like arthritis, worn out ligaments or other ailments which cause a need for a changed swing to improve or keep up there competitive level.