I (and people like me who are older) may have less tolerance for nonsensical non-fun time sinks because we view our time differently than younger people who are used to not getting paid (or not paid well, at least) for their time. The act of gearing up isn't fun (especially in MoP) for us...it's a gate we need to unlock to do the thing we ENJOY, which is raid or PvP.
Now, as I said before, there's a problem currently where the actual raids and pvp aren't really as good as they should be...or can be. The problem is (as people are wont to) we remember the good raid bosses or pvp encounters. So we think "man I want to get in there and kill me some cool new bosses" or "man I LOVE playing RMP" or whatever...but when we get there (finally, after the non-fun gear grind) we're let down. And quit. Because it's not fun. Not because "I'm not progressing my character" as such, but because they're not having fun (even if it's just because the only fun they HAVE is progressing their character).
For me, getting gear was nice and all...but I wanted to kill bosses. I never liked farm nights. I liked progression nights.
Assuming the boss wasn't trivial or in someway poorly constructed, anyway. And there usually were a few of those and a few good ones in each tier.
For me, I'd be OK with a tier with ALL the bosses like h-Rag...ones that take MONTHS to kill, even for good guilds. I'm perfectly ok with killing a boss once and just moving on.
And if PvP weren't obnoxiously annoying with all the problems that plague it nowadays, I'd be perfectly cool just murdering other players over and over because it'd be FUN.