[mattnewton]

It’s more that there is no function that discriminates against a given kind of spam without a false positive rate, and after you implement it, the scammers can just switch techniques to another while now you are continuously dealing with the false positive rate of your method. The attack surface is nearly the entire human language and we’re not good enough yet at understanding if it is a scam in a scalable, automated way, so we have to keep bolting on things with false positive rates that cause support tickets and lower engagement over time. This is an incredibly hard problem.