I disagree, I think you are only using your own anecdotal experience that flies in the face of my own anecdotal experience.
There are differences between communities between different games. This is all simple demographics. Certain IPOs attract audiences from different backgrounds and at different ages, this leads to different communities.
Take, for example, when MMORPGs were first a thing (Early MUDs/EQs, up to the very early 2000s, maybe including XI). High speed internet was rarer than it is today, so those early adopters tended to be tabletop afficionados with the disposable income to meet (at the time) quite high PC spec requirements. These generally meant an older demographic with experience at socialising while RP'ing. These tended to be more friendly people (even when they were PK'ing you). Yoshi-P recently described his first experience at getting PK'd in DAOC and how that person took the time to tutor him.
Then enters a game like (for example) Star Wars Galaxies. It shares much the same community as the first generations of MMORPGs (essentially nerds) but with a significant portion of players drawn in by the recent Star Wars prequels who tended to be a lot younger. A lot of guilds introduced minimum ages when recruiting to cut down on smack-talking 13 year olds.
Other games were introduced that catered to different niches (FFXI for nipponophiles, EvE for Iain M. Banks afficionados) and the games' communities tended to reflect the niches they attracted (very polite JP; every party starting with ohayou, many congratulations when people dinged etc in XI. A generally, more sober, mature and ridiculously meta community for Eve).
As WoW brought online MMORPGs into the mainstream (as mainstream as pretending to be an Orc fighting Pandas is ever going to be) and high speed internet becomes almost ubiquitous, more and more people enter the community without any experience of the once-standard MMORPG etiquette, that etiquette starts slipping away. I remember the lols when I said 'ding' once I levelled in GW2 and the confused responses when I congratulated people when they hit a relatively insignificant level.
Then as Guild Wars ushers in the age of F2P MMOs and MMOs start catering to the (now huge) community's demand for games that are easier to pick up and put down (no/little death penalties, automated raid-finding), the genre becomes attractive to those that don't have disposable income for a sub and want more instant gratification. You know; kids and young adults.
This reaches its nadir (hopefully) with LoL. A game which requires no investment to get into, no repercussions for bad/rude behaviour and little to no chance of meeting players you don't like again. This game's community is known far and wide as being incredibly rude and childish.
If I were to sum up my own long, rambling monologue into a tl;dr it would be thus:
tl;dr The wider an audience you aim for as an MMO developer, the more negligable you make the non-raiding experience and the less responsible you make the audience for their actions, the worse a community that will result.
So... make a really niche game for really old people, make it punishing as hell and make it community driven and give it a sub. The result will be a great community (I think I just remade EvE).
THIS I have never told someone that I hope they die. I never saw it or heard from another that they saw it in XI, SWG, UO EvE or X|V version 1. I saw it very occasionally in GW, a bit more in GW2. I see it weekly now in DF and hear from others they see it often too. There has been a change. Believing it isn't so is, in my opinion, being disingenuous at best, willfully ignorant at worst.
