To quote my comment there:
I fail to see how this relates to quantum computing. I think you're just asking about supercomputers in general, which quantum computers may happen to solve. In my mnd, that's analogous to asking about how electricity works on SO.
Your question seems to be about solving complicated problems (i.e. many-body problems) using quantum computers, with the emphasis on the quantum bit being helpful for that problem. However, I'm not sure why you think that personally. I don't see how quantum computers relate to solving hard problems, and you failed to provide that explanation.
My intuitive reasoning behind that, using quantum computers we can essentially simulate a quantum many-body system, making the theoretical calculation in essence to an experiment.
Why can't a Really Really Good Supercomputer™ that doesn't use QM do this? Quantum computers themselves aren't the genius solve-all that you seem to be treating them as. This question doesn't really rely on quantum computers to solve your problem, and it's not about quantum computers themselves, so IMO it's off-topic.
I would have voted to close as that in the beginning, if I actually understood your question. Since then, I can't retract my vote (and vote again) to change the aim of the vote, and I'm not planning on it.
P.S. if it took a meta post and a couple edits to get your question understood, and your question was closed "surprisingly quickly", you may want to revisit your question-writing practices.