Quantum computing doesn't solve all the problem. Some crypto are quantum-resistant while others not. Additionally, it has its own complexity, not everything is O(1), and there may have some errors during the calculation.

The initial idea of Nakamoto was great. However, you need an interface between our money (Dollar / yen / euro) to buy it or exchange it against goods, which makes it prone to state taxation / regulation.

So now I see it less interesting than option trading, as you need to put your hand in the dirt to get your crypto, keep your private key safe, etc. for at the end having the same legal obligation for tax income.