Reply blocking should only be useful when someone is actively trolling your page people. When they disagree with you that is not trolling or harassing, it is having a different opinion than yours. Seriously that is like walking away from an discussion without having the other side give their proper account of their own opinion. It's cowardly to reply block, basically it's saying "I don't want to hear the validity of your own point blah blah blah I'm not listening!" It's childish to just not allow the opposing side their own defence of their viewpoints.
Also people really need to research the report process more, having a different opinion is not trolling or harassing and therefore is vindicated. You cannot just report someone who you are in an argument with if they have a valid point, (or at least a point they are standing on with legitimacy.) That is like getting in an argument about a trivial matter on the street with another person and then running to the police like a child who runs to his mother to tell on their sibling. The Deviantart Administration will only take your report request into consideration if someone is actively harassing you personally with malicious intent, and having a different viewpoint and arguing with you in a civil matter is not malicious intent.
Some people need to grow up and learn to handle a civil disagreement properly.