As a tank main, I find nothing wrong with tanks in their present form. I don't need to do giant dmg numbers to stroke my epeen. It's enough to know you wouldn't be doing ANY dmg if I wasn't holding the mob for you. It also feels pretty boss soaking up 5k+ crits and not folding up into a tiny ball on the ground (thank you for continuing to heal me).
The main reason you see so many complaints is because people honestly think ALL you are expected to do is the halone combo... there's several other skills that are in constant use, plus smart usage of your dmg mitigation cooldowns, plus being expected to be constantly aware of all party member's current location for mob positioning, plus holding hate off multiple melee that couldn't hit the same target to save their lives...You are usually the person expected to mark targets (provided there's anywhere left you'd actually NEED to at this point)
All this responsibility, and the ease of dropping and instantly getting another pt, turns a LOT of tanks into complete jerks. Personally, I haven't had many people throwing hateful comments my way, so that's not really an issue. The only thing I detest, is people seeing me in ilvl90 and automatically assuming I need/want to do speedruns in duty roulette. If you pull expecting me to SR you, expect to tank em yourself.