There has only been one occasion where I witnessed someone being harassed by someone else using a parser. And, in my honest opinion, they deserved it. When you go into level 60 content with full end game gear and your dps is less than what it should be for your class at level 50, there is just absolutely no excuse for that. If you want to play however you want, that's fine if you're doing stuff on your own. But when you want to play with other people, it's incredibly selfish to expect them to carry you because you can't be bothered to improve yourself. It's a shame that this game has such a huge skill gap and people would rather run and cry to SE to stop people from telling them they need to improve instead of actually improving.