That depends upon the bullet. The military tests only showed about a 3rd less wind drift. I have no trouble shooting 1,000 yds with a .308. But, if I need to consistently shoot a mile using anything less than a 50 BMG, I wouldn't be doing it with a Creedmoor. I'd be using a .338. But, that has nothing to do with which one is a better SHTF gun. For now, the Creedmoor loses on that aspect. The 6.5 CM has been around since 2007. Give it some time. It might catch on this go-round and become widely used enough that ammo and guns for it will be plentiful, varied, and cheap. But, the one thing it has against it compared to a .308 is short barrel life. That's likely what turned people against it when it was first introduced.
I don’t find barrel life bad. I have chronographed my factory loads at 2682 (hornady eld match 140gr). I made some handloads with 147gr eld match, and came in at 2710.
I’ll probably build a 300 PRC this year for more range, but you’re right, there are better choices for a mile and more.
The US army is using 6.5 in some application, so it’s definetly going places. They had a team shoot a range with their semi auto 308 (Think it was seals if memory serves) and the same team went through the same range with 6.5 semi and scored 50% more hits. I’d have to do some digging to find the article again. Reduced recoil and high ballistic coefficients combined with a good velocity equals great stopping power.
I like to bring up the benefits of the 6.5 because gun people are like horse people. “if it’s not a quarter horse, it’s not a horse.” that’s the way it is up here in rodeo land anyways. A lot of guys including myself would say it’s not a battle rifle if it’s not 308. I’ve since changed my mind, proving that an ol infanteer’s stubborn attitude can be overcome heh.