I do not understand why so many people feel the need to mock others who have different gameplay preferences. This goes for both 'sides'. Just because a player spends most of their time in PvP and has low DPS in PvE content doesn't mean that you should shame them. Just because a players spends most of their time in PvE and doesn't understand the mechanics to PvP doesn't mean that you should mock them. There are times when players are basically forced to engage in a gamestyle that they don't necessarily enjoy (such as when PvPers have to run dungeons to level their undaunted passives or when PvEers have to run battlegrounds/Cyrodiil to level their alliance ranks for Purge/Vigor/Warhorn/Barrier).
Just because you come across someone who is not performing well in that environment does not mean they are a bad player. They might already not be in the best mood since they are having to do something they don't want to do (such as leveling their undaunted or alliance ranks).
PvP and PvE are two sides of the same coin. Rather than piting ourselves against each other and mocking the content someone prefers to play, why not have constructive conversations? If you see someone struggling in PvE, rather than saying "delete your build lol get gud" why not give them helpful feedback? Ask them about their build. Help them with their rotations. When you see someone struggling in PvP, instead of saying "lol get out of Cyrodiil idiot" why not give them advice? Why not compliment someone who attempted to fight back despite not having great gear or combat awareness? Why are so many player's initial reactions to belittle, insult, and provoke others?
"Lol it's an online game, if they can't handle the trash talk then go play Skyrim"
"Lol but they're bad so they deserve to know it"
"Lol they need to grow thicker skin"
Whatever happened to respect? You don't even know what that person has been going through in real life before you decided to make that rude comment. Many people play video games as a way to handle stress and relax, so you don't know what type of news that person might have received right before you told them to "lol just uninstall the game" or "lol just kill yourself PvE noob".
Consider the weight of your words. Consider how you might be able to help someone who is struggling with content. Consider how you might be able to make the game more enjoyable for someone else. Just be considerate.
Before the trolls and baiters derail the thread, I hope that at least some beneficial/constructive conversations take place