These days given red trusts may be generally accurate, but on my short research I found at least one, who is also flagged as "third world shit poster" without spamming, who accidentally went into crossfire on bitcoin discussion.
False positives will occur in just about any system. As long as their percentage is low enough, it is fine.
If my perception is right, then red-tagging is not 100% accurate? And some of the tagged members might not be involved in shitposting or any event that had led to tagging?