I respectfully disagree with most of this. The 7mm Magnum is not an inherently inaccurate cartridge. I have loaded for several that have been boringly accurate, including my current one.
The .300 WM is a great cartridge as well, but offers little ballistic advantage in factory twists and noticeably more recoil than the 7RM.
I have also owned several 270 WSMs that I really liked. The cartridge is certainly capable of your uses, when loaded correctly. However, both of my 270 WSMs were tough on throats and long range bullet selection is tiny in comparison with 7mm.
I actually think the 270 WSM is a great MPBR cartridge since it shoots flat out to moderate ranges.
That's alright haha I like these types of debates/conversations. But I don't mind recoil. So my 7 3/4 pound (scoped) 300 WM is great. I'm just saying my friend loves his, but can't get tight groups with any ammo. And I have HEARD it is wild. That is just what I HEARD. It is obviously popular for a reason. I have even considered a 7mm just because it is so popular.
And for long range uses, .270wsm is great. I was assuming he reloads, since it seems like everyone does on here. The 7mm drops slightly more down range, but nothing too drastic. The short action would be a plus (in my mind) if he is "hunting off his back", in a mountain rifle setup.
If a guy reloads, the bullet selection isn't that small. But still gotta stay 130-150 grain, matrix etc. But you may need a different barrel twist with those bullets. I'm sure you have more to play with in a 7mm.
I do think both cals in a 24 inch barrel setup, the wsm takes it. It's ballistics will be equal, if not a bit better in usually a smaller rifle.
Now if you are talking 26" barrel or more, that's another story. 7mm would beat it at the range.
Like I said, I prefer my 300 win mag. But with either of these cals, the elk/deer/hog/lion etc etc will all be dead the same and not know the small differences.