there is nothing you can do to fix this unfortunately. The problem is not the tank job selection but rather what the job represents, and that is responsibility, party awareness and the ability to learn a battle faster than any other role in the game. Then coupled with the fact that people will have personal preferences and bias' and you just narrowed the selection of people who are willing to take tanking up as a main. I myself am a WAR main but I also make sure to level the other tank jobs so I have a rounded feel for the role and can adjust if needed. I love to tank especially as WAR because seeing high hp and damage are my two favorite things in any game. However given the community ridicule towards tanks, especially in df, I can see why it's an unpopular role. Nobody likes to be ridiculed or called out but most of us tanks had to deal with it at some point.