I was once semi-surrounded by coyotes while hiking in some back country with a friend.
I did not have anything except my camping knives and a very small axe for splitting kindling.
My buddy had a compact 9mm in his waistband.
Honestly, I can say an AR would not have made me feel safer. A larger capacity on my sidearm, on the other hand, would. The AR is just too bulky to move quickly in close quarters.
Luckily a single round to the trailside was enough to scare them off, since yelling and throwing things wasn’t. We then ran/sprinted a few miles down the trail toward the vehicle before we even considered slowing down.
Not many situations in which either one is something I’m desiring though, and while I’m not a fan of limiting people, I can’t say I’ve ever needed 30rds at once. Honestly, I buy 10rd mags just because they fit very nicely in some cases I already had, and the 30rds don’t.