The metal detecting forums sure did gets nasty at times. There were detector wars over brands, over finds where some were accused of lying, the relic hunters laughed at the coin hunters, the coin hunters hated the relic hunter. I had seen at least 2 forums get into such a war, that most people quit and the forum died. So, what changed all this fighting to almost disappear?
A metal detecting forum was divided into relics forum and general hunting. Sub forums also showed up....beach hunting, make of detectors, followed by model by make forums. Rules were made, and enforced. For a while, people could change their name and quickly get back on. Better technology allowed this to be harder to do. People not following the rules were sometimes banned for a while, or life. Some banned members joined other forums and denounced certain forums. Eventually, things settled down, and as more experienced users filled up the forums, the old "mines better then yours" kind of disappeared. Then forums got volunteers to act as moderators to enforce some of the rules, and maintain peace. Findmall and many other forums seem to run pretty smooth. People with too much of a bad attitude tend to get ostracized and either leave on their own or get their posts removed at times. Generally, most posters here like showing their finds, give advice and compliment other's finds.
But, there are still some forums out there where all hell breaks loose, usually over detector wars. There are trolls on these forums that like to keep things in constant state of discontent. The bad guys stay there, and a lot of the better users move to other forums like Findmall.