I believe the main reason a long range hunter would want a large caliber for elk is to eliminate as many enviromental factors as possible while delivering as heavy a blow as possible. Wind velocity and direction is a constant changeing factor in the places elk live. With a large caliber, high B.C. bullet, you get better retained energy, and more down range velocity which in turn helps that bullet to open and deliver that energy inside the animal, and hopefully exit, leaving a good blood trail. In long range hunting, it may take quite a bit of time to get to where the animal was when you hit it, and the more damage done, the easier it will be to recover that animal.
You can't kill what you don't hit. If someone can shoot long range succesfully with a smaller caliber, and can't take the recoil of a larger caliber, then choose the best bullet for the range and animal being hunted, and go huntin'.
My wife shoots a 270 win. and is deadly out to 900 yds... She can also shoot my 338 Edge better than I do. But she only shoots at game with her 270 cause that is what she is more confident with. And confidence and abillity with any caliber leads to meat in the freezer at any range.