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.
I have never thought of the
economics aspect towards how the Quantum Computers are going to be a threat towards the different kind of computing systems. I agree that the ones who can be the first customers of QC's might probably be the richest people. Addition to the people researching on that subject, they are going to be the first ones.
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.
I know that we are far away from that reality but preventing the possible QC attacks to the network is more viable. I'm just not sure how they are going to do it because knowing the computing capabilities of QC, and it could outsmart any problems faster than normal.