First of all, we have to make reasonable inferences of intent all the time. Being able to do so lies at the heart of criminal law (see mens rea). We'll never be

First of all, we have to make reasonable inferences of intent all the time. Being able to do so lies at the heart of criminal law (see mens rea). We'll never be able to probe into the subjective heart of someone, but we do our best based on available evidence and tolerate the errors, while always trying to converge closer to objective truth. There are plenty of interesting things to talk about in this world. Not all comments are worth publishing or reading; some are deemed more valuable than others. Editorial discretion is one of the distinguishing characteristics of different discussion fora. Just like you could read a different newspaper if you disagreed with the editorial bent of one, a great thing about the Internet is that you can always start your own forum if you disagree with the editorial choices of an existing forum owner. And the startup costs are a whole lot lower, too.