Nonsense. RealID allows you to keep in touch with people, yes. However, when a large part of the game can essentially be played as "single player", for many people there is no *push* to interact with others in a positive way. Just look at the cesspit that is LFR; you have bad players winding everyone up, average players staying quiet and just trying to get shit done, and really good players yelling in chat about how amazing they are and how everyone else sucks. Nobody is having fun interacting in that environment.
Yes, finding people to do dungeons with in the past was a little bit of a pain sometimes - but that encouraged you to seek out a decent guild, head over to your realm forums to introduce yourself and find people to play with. In TBC my realm had a massive unofficial forum, that we the players paid to keep running ourselves. Everyone knew everyone, so finding groups if you're a nice person and an even half-way decent player was not that difficult. Cross-server random LFD doesn't do that. You just queue, finish the run in silence, and leave.
If LFD had been same-server only, you'd have a point because then you'd get matched regularly with players you would see running around and the interaction/need to get to know people and not be an asshole would be there. In its current form, it doesn't even discourage you from being the biggest bellend in the world thanks to the ridiculous long-cooldown kick timer and often-times being unable to use it.
I'm hoping that with flex, and the return of same-community pugging, we'll get a bit of that TBC/Wrath community back, where the jerks are shunned and the good & nice players all get to hang out and have fun doing stuff. You won't be able to convince me that I should ever run LFR again when flex comes around.