DM
the performance difference may be more due to specific bullet selection than the caliber attributes.
I think that with the 270 people gravitated to the 130gr ammo because that is the most common green box stuff at any local store. That is not really the best all around performer. I know several people who complained that the 270 was inadequate and either ruined meat or wounded game. All were on deer in NY, where shots run 30 - 100yds.
Had they bought 280 or an 06, the most common available green box stuff tends to be heavier for caliber, and better for these shot presentations. Not a fault of the caliber, more of the hunter andof the marketing managers who choose what these big box stores carry as their low price ammo.
I agree with what you have said... BUT, i'm not the average Joe who goes out and buys ammo. I spent many years testing bullets, i also did some design work, and mfg'd bullets for my own use and sale...
In my testing there seemed to always be certain bullets/calibers that worked waaaay better than expected. For instance, the 30 cal. 200NP... In a 30-06 it just flat out, performs better than i ever expected... Much better than anything else i tried. It will give some expansion on smaller animals, yet stay together and drive in to break both shoulders on a big brown bear.
Another is the 7mm 175NP... This bullet works waaaay better than expected, and in fact the 7mm "caliber" just plain works better than expected. 175NP's would always expand and still out penetrate 375's and .458's in big bears.
I'm no longer into all of that on a big scale, but over the years i did learn that when it came to deer, the 280 will do anything a 270 will do, and when it came to something bigger than deer, the 280 would out perform the 270. Yes it's because of the bullet, but none the less, it did it for me.
A perfect bullet to me is one that expands fast for small animals, but will still drive all the way through a big animal. In all of the years i've been harvesting game, i found it's best to have an exit hole. Bottom line is, 7mm bullets have done that better for me than 270 bullets...
DM