A long time ago (in my first MMO 13 years ago), I got annoyed when people told me how to play my character. But as time went by and I got to know the game, I understood that many people don't tell me how to play my character. Instead, they are trying to help me improve.
I think many newbies mix this up (though it also depends on how advise is given). Especially since FFXIV is one of the few MMOs available for console, there are quite a few people for whom this is their first MMO. Usually we try to help these people when we encounter them in a party. We give them advise and hints, sometimes even try to make them realize in Sastasha that their god-damn PLD is NOT A DPS! But when you don't see any of your advise being taken as the dungeon progresses....it does get frustrating.
Unfortunately, in FFXIV, this happens very often. People don't listen, PS people have their chat closed for w/e reason and things go...bad. If a player leaves at that point, he is not an elitist or a jerk.....he is just FRUSTRATED! I never understood this as good as in FFXIV. I am a patient person, I try to help people, I often even heal idiots when I am not in a bad mood but at some point, I reach my limit and leave or kick then. I don't think I am an elitist because of that. In fact, I am not sure if I can count myself elite (I don't do or care for coils) but I think I am a fairy good player.
But people don't get good just like that. It takes time, effort and willingness to learn. That being said, my time is limited these days. On a working day I get to my PC at 10 PM and I go to bed around midnight. The few things I can do in that time are precious to me and I want to enjoy them, not get frustrated by a person that has no intention to improve.
I am not trying to force people to read guides but if you enter content, try not to be a liability and listen to what more experienced players tell you. Don't call others elitists because you suck and they don't cater to your whims.