There might be a dozen world cup DH courses where they wouldn't cope but for everything else they would be fine.
I can see what your trying to say, but an example…now i used to race downhill at expert level (until it got too expensive). After i sold my dh bike i was left with an orange 5. Great bike, but even on my local inners dh trails was left wanting. You cant really attack fast or rough sections on a 5, just ride them. That may be fine for most, but not when your used to racing! So i sold up and got a spicy…the spicy only has a little extra travel but feels so much more like a dh bike than the 5. You can ride it more like a dh bike, yet it still climbs as good (if not better) than my old 5. Moral of the story…if i still had my dh bike i wouldnt need a spicy, but i dont so i do!