Aside from crocodilians, aren't your biggest dangers from nasty little venomous buggers? Well, and the infamous Drop Bear, LOL! I think a .22 target pistol or rifle has a place in a survival kit due to the low weight and bulk of ammo. It can be used as an SOS audio signal, foraging for small game, and even emergency use of the gunpowder to start a fire. Your mileage may vary, of course.
Ideally, one would retreat from predators. Humans aren't usually selected as food, so the biggest danger is a mama protecting her babies. Believe it or not, moose scare me more than bears. They DO NOT GIVE A FUCK and will end you.
Crocs yeah, other things like razorbacks, cassowary's, dingoes, sharks and all...But generally crocodiles and sharks are the only two that will actively hunt a human. There's plenty of other things that'll mess up a human but a gun won't generally help with those.
I sold my .22 rifle and handgun a little while ago as I'm looking at other options moving forward so currently don't have one and wasn't about to borrow someone else's for Billy to shoot. I'm not a big fan of borrowing other people's things.