I've played both WoW and EQ2 extensively. I can assure you that both games are packed with idiots, though more so in WoW just due to sheer numbers. Each WoW server has a shitload more players at any given time than any EQ2 server.
WoW is easy to learn to play, enjoy, and even master. You buy the game, pay your subscription, and simply enjoy (in recent times you also have the option to buy one expansion pack). It's easy, it's convenient, and it just works. If you need any info or help there are loads of web sites to peruse.
With EQ2 in addition to the actual game you have the option of three expansions (soon to be four) and three "adventure packs" each available individually. Gameplay is not as easy or straightforward as WoW, and even if you do your research online you won't find that much available. Furthermore, each expansion or pack adds something to the game mechanics - two of the expansions are essential because your character will be grievously underpowered without the Achievements system they introduce (achievements are very similar to Talents in WoW, but you don't get that functionality without the KoS and EoF expansions). None of this is immediately clear to EQ2 newbies, especially because SOE has the bad habit of selling games at a discount to attract customers, who then find out that if they want a decent experience and a choice of more than four areas they'll need to invest muchos bucks in various add-ons. (It's nice that Blizzard sells a complete game and doesn't stiff customers the way SOE loves doing).
People who play EQ2 tend to be more dedicated and consequently a little more serious, more mature (mentally if not necessarily in terms of age). The game requires much more effort, money, and thought so that it becomes more of a process than the incredibly accessible WoW. That might explain the incredible number of idiots on WoW - that and the fact that the servers are just far more populated on WoW.
I'm not saying one game is better than the other - I am simply saying the differences in populations and the required dedication account for the incredible stupidity you are invariably exposed to in WoW. When playing WoW you really need to use the ignore function, disable chat channels, and find yourself a good guild and friends.