Tanks have a bad reputation because a lot of them indeed goes through the 'you guys need me more than I need you' routine. That's why it's also not really worth it to argue with them in the first place because you really do need him more than he needs you because of the shortage of tanks. Outside of Aiatar, I can't think of a fight that's just borderline impossible with a bad tank, and I've beaten Aiatar while the tank takes every single dragon breath. If your healer is halfway decent and your DPS don't suck, it shouldn't matter what the tank is, or is not, doing. I've had tanks who point Anantoboga in totally crazy directions but you can usually still get out of the tail sweep on time, and even if not, eating the first tail sweep isn't going to wipe you and you most definitely should avoid all the sweeps after that point no matter how weird the position is.