I'll give you my perspective.
This game is easy once you've had a chance to experience something (a couple tries, a couple wipes, and you learn how to beat that boss or clear that dungeon. maybe a couple more tries to know how to clear it fast). Well with duty finder, there's a good chance you'll have someone's first attempt. It's a bit of loop of people learning. I see comments about players sucking (not from anyone specifically), and I just think putting into the perspective of all your first time tries and how they went, you should be able to sympathize.
Now if you were the type that watched youtube videos on every single dungeon run and boss to be able to prepare for it, fair enough, but some people want to have the experience of trying and learning.
Everyone has been really nice I met in general (except a couple one offs) and no one has freaked out on me for being new, but I do see a bit of elitism with comments all over the game, and wanted to just point out perspective.
And if you are tired of playing with new players, then the only option is forming a static group. I understand that frustration, but some sympathy (not saying you don't have any, just a general comment) is also nice.
*I went on a bit of a rant. Sorry about that. I have just reached end game and been feeling bad every time I do an event as it's new to me and it's inconveniencing others (they don't say it or anything, as everyone has been nice).