Comment by beloch

While some forums had up-votes long before reddit came along, it was reddit that used them to rank and promote posts/comments. This provided some benefit, but also opened up a huge vulnerability. It became easier to find high quality posts some of the time, but it also drowned everything in a sea of karma-farmer spam.

Reddit also never found a good solution for moderation. Like the BBS's and message boards of yore, reddit mods are unpaid (by Reddit at least), anonymous, and unaccountable. Some are good. Most aren't. Modding is not a pleasant job, so it's worth asking why somebody would do it for free. The actions of some reddit mods can only be interpreted as psyops for authoritarian regimes.

Ranking and moderation remain tough problems. Algorithms can be gamed. AI, to date, has lacked the judgment to do either well. Humans can't be trusted not to behave like tyrants or push an agenda, either theirs or that of someone paying them. Not without costly incentives, like pay, and standards that are actually enforced by other humans, all of which is expensive.

An oldschool forum without up/down-votes might actually be less susceptible to karma-farming. No karma = no karma-farming. However, you're right that giving up everything that came with karma systems is tough to do.