Half our new recruits literally quit and never log in after their first week.
I'd imagine them thinking "wow endgame is THIS recycled crap? hardmodes a tiny bit of atk/hp and still easy? I'm outa here"
Tanks are rarely in need as you say, 3 tanks + 22 randoms is what makes a 25man raid you should've seen how hard it was for a warrior to get a guild in BC regardless of his skill level while prot pallies and shamans in t4 who are mentally handicapped were invited by the droves by t6 guilds.
cataclysm will give you the 10man progression design where it's 2 tanks + 8 randoms, so more spots will be available for you, don't roll new alt if you find them boring, leveling sucks.