My first semi-auto was a Jennings .22. It was reliable about 50% of the time, so it quickly found a home in a box.
(My first handgun was a Ruger Single Six, both cylinders.)
I knew a guy who carried a North American .22 mini-revolver, a tiny thing, and that as his main carry gun.
I suppose the tiny size would make it easier for someone with a real gun to take it from him and shove it up his ...
My backup now is a Springfield XDS .45.
If it’s going to be a: “He had a gun, and the other guy had a gun ... “ narrative, and the other guy has a real gun, why would you want to be the guy with a ‘mouse gun’ like a derringer or .22?
Just saying.
At one time I owned well over 200 guns, most of them handguns.
I would guess in my lifetime I have probably had over a thousand. I did a lot of trading and swapping.
I have owned several Jennings and every one was totally reliable tho it would not surprise me if someone had one which wasn’t.
My carry gun most of my life has been either a 1911, a Browning Hi-power, a Sig P226 or a Glock 17 or 19. Many others would do as well.
I am getting to where I don’t do much hiking but when I did, I usually would just put a Walther PP in .22LR in my pocket. It doesn’t hit hard but it hits hard enough.
There are plenty of reasons to carry a tiny gun, most of them being for back up.
If someone was holding a Beretta Jetfire in .25 auto on me, the last thing I would try to do is take it away from him. If I did, he just might put 7 bullets in me for my efforts.