Autofishing is a bot on its own, does not require any software.
Sport fishing?
I dont know.
But
hackers do.
Thats why admins are taking care before making any changes.
Not saying they should not buff it, just need to find a smart way on how.
The screenshot you linked to is discussing a plugin that will fish for you, but does not take care of any of the other steps involved. It's a part of ArcheBuddy (which doesn't exist anymore, so I don't see a problem discussing it here openly). When it still worked, the only thing that this "plugin" took care of is fishing itself, after you've cast and before you have to go get the fish out. I've seen the videos demonstrating what this plugin did. And it did not do everything for you, not even close. And it didn't even do it as efficiently as a player who knows how to fish can. And that's if you could even get it to work considering ArcheBuddy has been shut down for quite a while now and has moved on to something else that doesn't support private servers.
So people who want to bot sport fishing would have to buy it from someone (and who can actually find one that does it all for you, which I have been unable to find, ever) or develop it themselves from scratch.
And even then, it's not going to do it as fast or as efficiently as a player who is there paying attention and using techniques that make fishing faster that are exceedingly difficult to automate.
It also doesn't take into account that bots are very bad at pvp unless they are super geared (which they never are), so making fishing better for players would increase the risk for leaving an unattended bot to do it and actually make any gold. There are much easier ways to run bots that make a lot more money (even if you buffed fishing gold) that are completely automated.
What do bots do? They perform routine tasks that are repetitive and usually don't change very much. Sport fishing is not one of these things. The reason that a plugin existed for sport fishing was because the act of the fishing itself was repetitive and easy to beat with automation. The bot receives the info from the game about what the fish is doing, the bot knows the counter, presses a button, and done. But the bot doesn't find a fishing spot, buy chum in vocation, chum the spot, summon its boat, stand on the boat, do the sport fishing, retrieve the fish, load the fish in its fishing boat, wait until the boat is full, drive the boat back to the fishing stand, turn them all in, and then go back. If you can create a bot with the kind of complexity necessary to do this and it doesn't fail after even 1 hour, I will personally endorse your application to NASA writing AI for space missions.
The likelihood of this being done is astronomically against. And don't you have to actually stand on a boat in order to cast a rod in sport fishing at the first step? I can't even remember now. I know you have to have good line of sight to the water, and I thought you had to be on a firm surface (not swimming) for you to be able to cast in the first place. Which means summoning a boat in the proper location, positioning it to fish from, and standing on it to fish properly (along with going out to chase the fish when it runs away).
ALL OF THAT ASIDE because I'm probably wasting my time with that:
The idea about reducing chum and lure costs is good. Maybe reduce cost of chum for vocation, but also make recipes where you can use fish caught from regular bait fishing as chum instead of making them into dawn lake essence. Probably cooking bench or maybe farmer's workstation. New players who are autofishing to level could sell the fish on the AH instead of making dawn lake essence to sell, and people would buy it to make their own chum.
Lures cost should be reduced in vocation, but could also make handicraft recipes where you can make them. You could build handicrafting proficiency or buy them from the AH from players who make them. Handicraft bench, obviously.
Fishing spot respawn time could be reduced to allow for more fishing spots to be up and ready to fish. Pack makers don't have to deal with the pack crafting station despawning after a certain time; the pack crafting workbenches are up 24/7. Miners don't have to wait very long for ore spots to come back. Both of those can more easily be botted and can be done almost without any stopping at all. If people didn't have to look for a fishing spot for an hour before being able to even start fishing in the first place, you'd probably see more players wanting to do it.
If there is a loot chance table based on proficiency, make high proficiency yield better returns. I can't remember at this point if proficiency determines anything about the kind of fish you catch, but if it is a part of the formula, make high proficiency a stronger part of the calculation by increasing it's weight in the RNG. Make it so high proficiency fishers are more likely to catch higher-end fish, while low proficiency fishers are less likely to catch high end things. This would also work against botters since they tend to be on the lower end of basically any proficiency except mining, commerce, and larceny.
Make sport fishing level 52+. If you can limit sport fishing by itself to level 52, bots would be less likely to do this until they've leveled up some other way, making them less likely to do sport fishing at all. If it can't be done without doing it to autofishing also, I'd say leave it alone. Let new players use autofishing to level.
That's all I have for now. Like I said, I don't mean any disrespect, but it doesn't make much sense to me to hear the reason for not fixing something is bots when I've never heard of or seen evidence of a bot that can actually accomplish it. They can accomplish parts of the process, but the process cannot be fully automated.