Great community!

[Jeeqbit]

There are a lot of reasons for it. There is no way to tell your damage output in the game beyond the enmity meter, which at best can usually just tell you who is doing most damage other than the tank (a yellow bar shows on them in the party list when an enemy is targeted). Dungeons are easy to the point that one good player can carry three people who don't know what they are doing and there is no time limit on the bosses, so high DPS isn't important. Everyone can see who is a new or returning player by the sprout or flower icon, which helps them to understand that you are new and to not expect you to know anything. They are used to there being at least one new or returning player because the roulette system matches veteran players with mostly first timers needing a clear, so they are used to someone dying. They get rewarded with tomestones or experience points when it is someone's first time so it benefits them for there to be a new player. There is the commendation system to motivate you to think about what someone did well, rather than to think negative thoughts.

Beside the game's design, it attracts a lot of people who have never played an MMO or just play casually, so a large amount of players who do dungeons are too casual to think in terms of DPS and optimization.

It is rare, but if you do run into someone who is rude, report them because being rude or giving you a bad experience is reportable.