there are people in swimming who specialize in certain strokes. breast stroke, back stroke, freestyle whatever. totally different movements.
i would compare this to shooting a 3-pointer in the NBA, dunking, passing, and defending.....it's all basketball to the naked eye.
imagine if there was someone in the NBA who could go out there at the allstar game and break the NBA dunking records and get perfect 10s every dunk, and not miss a single shot in the 3 point contest, and then easily be considered, by far the greatest defender of all time, and easily by far the greatest passer of all time.
in baseball, easily the fastest runner, hit the most and furthest homeruns of all time, have the best glove of all time, etc.
in football, be the best passer of all time, plus the best runner of all time, plus the best receiver of all time, etc.
that is what i equate what phelps is doing to. he is breaking world records, owned by different men, every time he races regardless of what stroke he is doing. and he's doing it racing back to back to back joining every different event, fatigued mentally and physically, and still breaking world records everytime out.
being the greatest ATHLETE has nothing to do with sport. swimming is certainly an athletic competition and i think everyone recognizes it as a sport. just because it isnt a very popular sport or you dont like his sport....and it isnt one of the big 3, doesnt mean he isnt one of the greatest athletes of all time. that is your bias kicking in.