As far as I know most Olypic atheletes buck the trend when it comes to BMI, either being under or over the "healthy" status.
I do agree too that BMI is a cr@ppy tool to use to reduce everyones weight down to. Its only one part of the equation.
Everyone is an individual, has individual requirements. For example it is known that some people can have more dense bones then others, some people have build more muscles then others, some people have a larger bust then other women (I knew a girl who even at a BMI of 14 (she was anorexic) had a bra cup size of a B/C. At a BMI of 20 her cup size is nearly an E.)
Add all those things together, and I am sure there are more, you get at best a very rough estimate and at worst a lousy if not even dangerous equation to suggest if someone is healthy. It does not make any sense to out everyone in the same basket with regards to BMI just the same as you wouldn't do the same for all women having the exact same symptoms of pregnancy or to say that every man heals a damaged bone at the same rate, each person is an individual, each will have an individual body, individual parts to that body and individual health weight.
Just my tuppence/2 cents worth!