I have not hunted coast to coast. I grew up hunting big game in Idaho. I started with a .270. I have watched my little ole mom kill more big bull elk in the 70s and early 80s with a .270 win in an old savage bolt gun and a 4x leupold than most of the "experts" have probably ever seen outside of the "game farms" or guided hunts.
Myself, I have only killed a dozen or so elk with a 270. I never knew I needed a magnum or premium bullets.
Since then I have used 308s, 7mms and the 300 win with good success, but none ever died any quicker or were more dead.
Same goes for mulies. I cannot tell the difference between deer shot with a 30-06, 270, 7 rem mag or 300 win mag. They all just died and the work began. Quarter 'em, tie 'em on the pack frame and start walking.
The only thing I have done is extend my range a bit.
I enjoy long range hunting but unfortunately the majority of hunters I see with "long range" guns have no idea how to utilize their gear and take very irresponsible shots, often missing the entire animal or worse.
It is a year round dedication to make long range shots on game in a responsible manner.