Don't think anyone with a mature sentiment would instantly insult someone new.
The premise of the thread is a life long MMO dilemma in which it can never be cured, 'Noobs/Newbs' how ever you want to label them will always be present in any community, you'll have a portion of the community that will do what they can when they happen upon them and the other half won't nor feel they want their own personal time being wasted by an an inexperienced player.
A lot of the hate derives from frustration mostly, I'd be lying if i didn't chuckle to myself on occasion after seeing a MNK try to DPS last boss in Tam-Tara continually thoughout the fight when quite clearly the words "INVUNERABLE" must have been spamming his screen.
The likes of PLD's spamming SB/RB and raging at DPS because they're losing aggro. Just some instances in which even after explaining I've had to /facepalm.
Quite clearly a lot of newer players do not invest their own time to read tooltips, if they did a high percentage of newer players with some form of learning curve would pick the game up relatively quickly.
It's a circle of appreciation in any MMO, if you're new, show willing and appreciation for other player's and the time they're investing in the group, then you will more often than not receive it back from the more experienced players. Speak up, tell them you're new, it avoids most altercations and if you're presented with advice that seems genuinely productive to how you can play, use it.
I personally have a lot of time for newer people, as someone stated we were all new to this game and all made mistakes at some point, I only find my patience wearing thin when it comes to higher level content and seeing people in full i90 / i100 gear that cannot play their class still or dodge things, (example- Duty roulette, Ifrit HM - DRGs/MNK spamming Leg Sweep / Steel Peak , players dying to IFrit's Dash etc , this is just a shortened example)
The game itself is probably one of the easiest's MMO's I've played in terms of mechanics and leniency to reaction and whilst like I mentioned I have time for newer players, I don't have time for Full Vendor geared players that repeatedly make mistakes or do not know how to utilize their class correctly. Unfortunately the game has bred these players due to the ease of access to gear, allowing newer players to pretty much gear their character in full i100 by just doing the main story and then farming 1 dungeon. They are then expected to perform to the standards of someone in that gear level and in a large number of cases are shown up to be otherwise.