Saying bows are better than guns (and vice versa) is like saying jackhammers are better than scalpels. Onebowonder is absolutely right in saying that they are just tools, each used to accomplish different tasks. Would I want my eye surgeon using a jackhammer to fix my cataract? Hellz no. And would it make much sense for a construction crew to try and break up the crappy sidewalk outside my house with a bunch of tiny knives? Take a guess.
I'll put it this way: I don't hunt as much as I would like to, and I've only been doing it for about three years. Hunting with primitive/traditional equipment is unlike anything else in the world, and I love it dearly. But let's say, for the sake of argument, that my family's survival suddenly rested on my ability to bring home dinner for the next month. Based on my skills (or lack thereof) with a bow in a hunting situation, I'll take a rifle any day. On the flip side of that coin: If I was in a scenario where ammunition, or God forbid weapons themselves, were impossible to find, I'd probably be spending a heck of a lot more time learning to shoot well with a bow.
I personally feel that I can make decent arguments for both sides here, not that it's really an argument per say, as I'm pretty well involved in both 1) traditional archery and 2) Tactical/defensive shooting. I'm learning how to make ELB's, as well as learning how to shoot from various points of cover or concealment. I finally learned how to make an flemish twist string, and also figured out how to clear a double-feed on an AR. (which, by the way, can be a real pain if you don't do it right
) In my opinion, they're almost completely opposite worlds. To me, archery is about the primitive senses, of getting away from unnecessary technology and getting back to your roots. Compare that to the style of shooting I'm into, where a piece of gear can literally be the difference between life and death.
TL;DR: Different tools, different jobs. One isn't better than the other.