For me an MMORPG is basically to games as a shopping mall is to ..well.. shopping.

That is to say, for me it's mostly a solo thing. BUT I enjoy the option to meet up with friends, or just do some people watching, or happen upon some interesting things like a flash mob.

I've been playing the genre for almost 20 years now and have played them almost entirely solo with a handful of friends peppered in. The actual people I randomly group with for DF in FFXIV might as well be AI for all the interaction we do in said duties.