I think the whole thing is a joke to be honest with you. But this is exactly what could happen as EU261 encompasses more and more things and excludes more things as an exceptional circumstance. When it does you will see aircraft continuing instead of diverting. Put simply the cost of a life to an airline (and we all know they'll have a figure on this) is probably less than a plane full of EU261 claims. Given what I said earlier, all it would take would be someone with deep pockets and a lawyer to take on their claim. If they win then you could find that medical diversions are no longer an extraordinary circumstance.
I say again, you reap what you sow.