I am a big fan of the .270 Winchester but I believe it falls at the bottom of adequate cartridges for elk. And the 30-06 is an improvement over the .270 for elk.
A game warden friend hunts elk with a .270 loaded with 130 grain Nosler PT. He is a cool, expert shot, who has far more field experience then most hunters. I purchased a 7MM Magnum for elk hunting because of its ability to handle heavier bullets then the .270 Win.
Frankly, the 7MM Remington Magnum was not my first choice for elk. The .300 Winchester Magnum was my first choice, but my dealer did not have one in stock. And he gave me a very good deal on the 7MM magnum. If I had owned a 30-06 at the time I would have used it or went for the .300 Magnum.
Another friend shot an elk in the front center of the chest with a 30-06 Failsafe bullet. The bullet penetrated the critical organs and stopped in a ham. Other friends have successfully taken elk with standard 180 grain bullets out of their 06. It is hard to beat the 06 as a good combination hunting rifle. (Did I just write that? 270’s rule!)