I felt the same way for many years. On elk and moose, the .30cals just seemed to do more damage. For myself and many others the 180grain Nosler Partition has been the benchmark for terminal performance.
When it comes to long range, however, there aren't too many folks shooting Nosler partitions.
Im not an expert, but around here it seems to me the benchmark projectile for long range in 30cal is the Berger 215gr hybrid.
At 600yd, I would rather be shooting one of those in a. 308win, than a 180gr partition out of a 300 win mag.
I agree - technology has improved. If applied appropriately, real gains can be leveraged. Unfortunately, that can take some trial and error - take the (7mm) 160gr Accubond, for instance. I have had markedly poor performance when engaging deer at moderate velocity. They just poke a hole. The target is too soft, and the bullet is too hard. Compared to a 140gr Absolute Hammer at high speed, the results couldn't be more different.
I've gotta say, for me,
projectile choice is more important than caliber (or even cartridge for that matter).
I haven voted yet. Kind of sad to see 30cal falling behind, but I agree with
@Ben Keller - recoil is a consideration.