One of the biggest attractions of EQ1 was it's endgame, and also one of the biggest disappointments, was the need to have very large guilds for the endgame content. These in themselves often grew to be large communities within the game, I've seen some as large as 300-500 active players (not alts/toons!). Back then, they were also very much non-elitist, they didn't care about your level or dps or stats, all that mattered was that you got along with others and wasn't an arse to everyone else. When the raid tool was implemented, guilds started getting smaller because the game had forced to limit how many people can be in a raid. 72. so guilds wound up splitting in half into those that were raid able and ready and those that were not. The invention of alt/feeder guilds is born move. The communities still stuck together out of game for the most part until WoW and other games started showing up. There was an old joke when WoW launched, "The average IQ of EQ went up 25 points!"
The appeal, IMHO and true for any game, isn't the "how fast you can level" or knowing that the devs are derps. The appeal is knowing that there are communities (guilds, the larger the better) to meet new people and make new friends. knowing that most of them will be there for you when you need help. This is what makes EQ1 still appealing to many, not the dated graphics.
EQ2, has become known as a crafters dream game with some of the best housing of any game in terms of what you can do with it, its only limited by the graphics quality. Its a game where you can be crafter and almost never go adventuring. The rest of the game is only there to keep from getting too bored. The latest expansion brought the Dungeon Maker, something that appeals to a person's creative side.
All in all, the old school games is what many cut their teeth on and we all know its hard to replace fond memories growing up in those games. It also spoiled many older games way too much, we grew to expect much more from newer games and the majority have just failed to deliver the content. Many Devs try to disguise new content and just copy and paste old content then try to put a face lift on the graphics (and then try to call it new). The appeal in recent years with any new game has become "how fast one can level or how fast you can beat an expansion", or even [insert compare to WoW comments], and still maybe for a few others, its prolly about how much they can cry about crappy content, at the same time finding another game to conquer. IF I was to offer any advice on what game someone should play, I would say play anything where you can make long lasting friends.