350 legend is a straight wall cartridge I believe--much of the eastern midwest and mid atlantic has limited gun hunting to shotguns or straight wall cartridges, so guessing there is a lot more demand for that stuff than folks from other parts of the country are aware of. Given we have no restriction where I live or anywhere I hunt I dont really ever see the straight wall cartridges. Not sure I know anyone who owns a gun chambered for one.
Bought my wife a 7-08 a bunch of years ago when she started hunting. My brother bought one right after that. Between the two of them, I liked it so much I bought one too. stuff seems to fall down when I shoot it, so no reason to complain, and I am past trying to prove anything so a girls or kids gun is just fine with me. I've never had any reason whatsoever to shoot an animal past 300-400 yards so I've never felt undergunned with my 7-08.
Also own a 6.5cm for PRS. Really the reason I chose that caliber had nothing at all to do with ballistics, it was simply that with every jill, harry, shiela and george toting one around it's much, much, much, MUCH easier to find inexpensive ammo to practice with than any of the other calibers I was considering, and if for some reason someone runs out of ammo or forgets at a match I can swap with nearly anyone there in a pinch. Maybe someday I'll decide i need to shoot a critter at ranges past 3-400yds, but until that day comes I dont think it makes any sense to worry about the minutia of ballistics between very similar cartridges like 7-08 and 6.5cm. My two guns would be wholly redundant except one weighs literally double what the other does and isnt much fun to tote around all day, and the other is light-enough that even in a supposed "girls cartridge" the cumulative recoil of 100+ rounds over a couple hours is pretty unpleasant. Edit: above statement is intended to say that in a 9lb rifle (or a 16lb rifle like my prs gun) 7-08 may be a tame cartridge to shoot as per reputation, but like anything else, put it in a very light weight package and it recoils just as hard as cartridges with a far more formidable reputation. I cant shoot 100 rounds through my little tikka without feeling pretty battered… maybe I’m just wimpier than your average girl.
I've never had a problem finding 7-08, mostly because I only really hunt with it so I only need a few rounds/year outside of some practice but I still buy as much as I can afford. I think I have a couple years worth, so unless this shortage lasts another 3 years I'll be fine. I worry a lot more about being able to buy 1000+ rounds a year of 6.5 at something less than extortionist prices.