I have played since launch, and yeah I feel it's kind of different now. I guess it's because im a much better player now and can find solutions to most of what I need to know online. Back in classic I often found myself solving problems with others in the game(was my first mmo ever). Also back then there were so many new people that took on the huge world in wow without any mmo experience before.
Now there are so many experienced players everywhere and over the years all/most of them got theyre friends on real ID and use skype/ventrilo/mumble to chat. Maybe the need to get in contant with new players is smaller now than it was years ago for those that have played since the start?
Personally, I am less social with "strangers" in wow than before. I got alot of real ID friends and a active guild chat, plus we are on mumble. So I cant say im less social, but I find myself not talking to much with complete strangers.