Additionally false negatives do more to lure people in to fraud than anything. By propagating false negatives the user base learns they don't always mean something and then genuine negative ratings blend in with the signal noise of frivolous ratings.
That's your opinion, and I think it's wrong. You don't know that members are seeing all these negatives and becoming immune to them any more than I do. The fact is that this forum is absolutely infested with scammers and dishonest people of all kinds, and the unwitting member needs to be warned about them. In other words, I think it's much better that one of these scammers or account sellers or what have you
has a red tag rather than not having one.
People can judge for themselves whether they want to trade with that person based on what the negative was given for--and if they disregard someone's trust, that's on them. Some people have to learn the hard way, and that's just the way it is. I know I did when I got scammed by a green-trusted member back in 2016.
Again, the pattern is complete dismissal of the negative impacts that false or frivolous ratings have on users. This is not just about one or two users but a larger pattern of this behavior which has a much bigger detrimental impact on the overall community. Users who are falsely rated with honest intentions will often just leave rather than deal with rebuilding their reputations while frauds are back in seconds with a purchased account. Negative ratings are handed out so flippantly to the point where they have become almost meaningless in spite of your pretense that this is not the case.
This forum IS infested with scammers. The problem isn't new, and shotgunning negatives at them isn't going to stop it, nor has it been. At best it will momentarily delay them. The question then is at what cost? I submit the cost is at the expense of the legitimate user base which has to deal with the constant fear of extortion via the trust system for saying the wrong thing. Some times they even get extorted using their hard earned reputations because they pointed out the wrong scam. Have you ever considered the security flaw of such a system in that context? What is preventing systematic extortion of reputable users here by using their reputations against them to keep them quiet about big scam XYZ if false negative ratings have no penalty or cost?
People can judge for themselves. The problem is the system is largely intended to help new users, and new users don't know any different. Again you point out another flaw in this whole argument. At the end of the day scammers can still hijack trusted accounts, making your shotgunning of negatives totally ineffectual against them in this context. Unfortunately for many people leaving negative ratings has become a game of quantity over quality, and for increasingly frivolous reasons which are indistinguishable from abuse, all done towards the end of increasing their own reputation as a "forum cop."