You’re not the only person in the group, and when you insist on wasting time, you ruin their game experience. This type of claiming it’s all one or the other seems a bit insincere.
The real problem is there are simply multiple ways to approach the dungeon. All “sides” are frustrated they can’t force others to play their style. Unless you make your own group to fill with others that want to play the same way.
It’s disappointing there are some tanks that really aren’t any good at dragging the size of packs they’re trying to drag. But that’s some players thinking they can do what they see on tv, not making the connection those people have a lot more gear and experience. Same as my little brother thinking he should kick my sister in the head cuz he saw it on Ninja Turtles. 
Bad tank is bad tank.