It's not the first time I read this kind of misguided arguments. Not all people enjoy the same things.
Myself I'm mostly interested in PvP, have all chars at 82+ with 6 at 85 fully pvp geared in the BG gear and I like BGs but I don't like arenas. What's the point in gearing up the few remaining chars I have left with a new PvP grind in BGs? Been there done that over and over.
Achievements have always bored the hell out of me so that doesn't interest me at all. I raided in Lich as a tank and I enjoyed it but I hate the changes to tanking and raiding in Cata so that doesn't interest me anymore. Mounts, pets, vanity stuff? Never been much interested in that, especially not after the first few mounts, titles and so on.
Questing? With all chars above 82+ I've done them way too many times and dailys are just an artificial time sink designed to make people go insane in order to get stuff I don't want as I wrote above.
Now then, tell me what I'm supposed to do in Cata? That's right, nothing and that's why I froze my account for 4 months after 4.1 and froze it again now, the game is just to linear for me at this point.
What I DID enjoy in Vanilla, TBC and for the most parts in Lich was:
PvP
Much more fun in PvP since the balance overall was better, no dumbed down BGs, old AV (need I say more?), no cry babies who destroy all that are fun about the old classic BGs, many more options in speccing your char for PvP. World PvP and world PvP, hey did I mention world PvP? Ganking wars when leveling, having to constantly watch my back and all that sort of fun stuff. Having to work hard for good gear and PvP titles really meant something other than "hey, I took part in a BG". Skill was overall more important than gear and broken class mechanics. Back then I could regularly out play many players that out geared me because of constant practicing and being PvP focused even in Vanilla where there was no resilience. Now you can just forget about doing well with certain nerfed classes and playing the OP ones require almost no skill at all.
PvE
Much slower and more fun leveling with dungeons being a challenge and not the "hey I dinged 4 times during this dungeon" express we find in Cata. Fun and easy going raiding (in Lich) as an alternative to my PvP activity. Quest hubs with A LOT of world PvP as a result and not the care bear solutions Blizz have implemented now. World events, outdoor bosses etc, etc and much, much better designed dungeons. PvE in Cata is just a snore fest to me.
The overall epic feeling and awesome experience I had in Vanilla, TBC and to a large part in Lich is totally lacking in Cata, two new races with the same old crap? Yawn, homogenizing of classes, roles and specs? Yawn, same old classes being op and the same old classes being nerfed? Yawn.
I can go on and on but I think you see by now that not all of us are interested in endless pet collecting, achievement hunting or crafting for its own sake.