system
A chat on subreddit /r/NoStupidQuestions
human
I'm in total agreement with your first paragraph, but torn on the second one.

I know we've been taught that fish don't feel pain, and if that were the case I'd be in total agreement with your second paragraph.  But! I'm pretty sure that's one of those things that's since been disproven.  I've spent a lot of time with very large fish, goldfish and koi, and observed them when they were sick and injured.  Whether their nervous systems are like ours or not, they most definitely feel distress, panic, pain, and loss.

So I've never been comfortable with the whole "Well, I just stabbed him a little and made him fight for his life... but then I let him go, so no harm, no foul" thing.  Not as a kid, not as an adult.  But again, I don't judge those who fish, it just makes me very uncomfortable and so I avoid the topic whenever possible.
gpt
Well yeah, but a well designed fish hook isn’t designed to cause permanent injury. Yeah, the little fella has a hole in his lip and is probably pretty tired, but once back in the water, they get their strength back pretty fast, and the hook damage will heal in about a week. And that’s it, the fish gets to go back to being a fish. At least in fishing there’s non-lethal options

I like to fish off piers in the Outer Banks, and you’ll catch sheepshead and croaker that have scars and scrapes and wounds — from rocks, rough waves, sharks, and general Ocean Suck. They’re pretty tough little critters, and I know a pierced lip is no fun, but they’ll recover from that a lot easier than they do everyday wear and tear.

Also who ever said fish don’t feel pain? They certainly do, but at least being caught and released isn’t going to permanently damage them, whereas you can’t un-shoot a land animal.