I think the nascent stages of a future currency, if it were to overtake a current one, would require the present currency system to be fundamentally broken. I don't see any evidence we're anywhere near that stage. I can trade my money easily for goods and services. I know the value of my money, and I can be reasonably sure it will retain that value over time.

If anything seems broken, it's a system where there's hundreds of currencies, most of whose values fluctuate all over the place. Why would anybody think we should prefer that to what we have?

Sure, there are certain situations where a stable crytpo like bitcoin nicely supplements the current system. But as far as it replacing it, nah don't see it happening anytime soon.