So are you saying that developers are going to use it for good or not? I dont quite understand what you are trying to say. With the use of QC, you would use it to see what type of attacks would work on Bitcoin and how it could be prevented? (Thats the good part).
Because of the issue discussed of only the wealthy elite being able to get their hands on quantum computers that are capable of threatening the algorithm Bitcoin uses its not realistic to use it for good. Especially because the easy solution would be changing to a different algorithm which would be capable of defending against a quantum computer. If someone wants to help Bitcoin against the future threat of quantum computers it would be contributing to the projects which are intending on implementing the quantum resistant algorithms or Bitcoin itself.