In all those games where they have such surveys i have the idea the information isnt being used. And the plain problem is that those surveys are often too basic to realy contain any good information. Only for the major issues those surveys can do something, but in most cases, the information is just too much cluttered to realy tell anything useful.

Good, we know people are not satisfied with healers... and now? Oh wait, its only 30% not being satisfied (50% of players said neutral and 10% showd satisfaction while not even playing healer). And then that value is higher than the 15% for other jobs. This makes it even more obscured. You need depth, which means players need to type their opinion, and this takes a lot of work to parse. Yet the main issues are already widely posted on the forums.

The forums already give enough information. You dont need more. If someone types here, he already took the hurdle of effort. So any issue in here, is an actual issue. How large scale it is you cant tell, but thats what you can at least investigate. Rather than relying on a random survey that tries to cover all, yet fails at it every single time.