This is just my theory, but I think most larger predators are just confused by us. We look weird, move weird, smell weird, sound weird. I think it tends to not fall into a neat category they recognize, unless they've had a lot of human experience as an individual or population. And then, they tend to view us as not-interesting (bears encroaching on suburban areas eating garbage), or potentially dangerous (wolves in places where there are armed ranchers).
If you think about it logically, even a big and strong human is not even close to a match to a pack of wolves, adult bear, or cougar. Firearms make it kinda better, but if they really wanted to take you out, most of them are capable of being shockingly quiet and really bringing the violence right quick.
Maybe we just don't taste too good.
I've never met a puma or a wolf pack. I've had experiences with black bears 3 times. I gave a sow with cubs a very wide berth, and she kept an eye on me the entire time. Once, the bear and I were both equally surprised, I was sitting quietly by a lake and had the wind moving away. He startled and crashed through the bushes huffing as I did the same in the opposite direction. Another time, I got a bad feeling about the way one eyed me from a football field or so away; I turned around to take a different trail, and warn other hikers that they probably wanted to do the same.