[gxiv]

> It involves calculating the inputs to a complicated mathematical process, based solely on its jumbled outputs.

Without going any deeper, this description of the problem is interesting because quantum algorithms are (by design) fully reversible, which isn't the case for classical computers (you lose information about the input when going through an OR gate, for example). Knowing that, it almost seems like a no-brainer that quantum computers would be better at this kind of problem than classical ones.

[zitterbewegung]

That's incorrect its a proof of probabilistic computers are unable to be faster than quantum computers for certain cryptographic problems (BPP < BQP) and has nothing to do with reversibility. The reason quantum computers must be reversible is quantum systems must be reversible.