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The bigger question behind all this in my mind is whether crypto actually solves any useful problem that anyone cares about.
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Very simple. Show me a poor, homeless person, that accepts credit or debit cards. In person cash works but over the Internet, across international borders? Crypto currencies solve this very simple problem.
I was also going to answer the unbanked. No need to be homeless. In many countries bank accounts are rare. In some countries where bank accounts are more common, fees are very high and there are lots of restrictions on international transfers.
https://en.wikipedia.org/wiki/M-PesaM-Pesa is huge, but run by the phone company and with much higher fees than bitcoin. There is demand for crypto!
Higher fees are kind of a weak argument. Bitcoin doesn't have a compelling model to scale up without enormous costs or becoming centralized (or both). So it can't really deliver low fees on a large scale either, or at least we can't say it can with high confidence. Now maybe it can with things like the lightning network, sidechains, or even long-term continuation of Moore's Law, but there is no real consensus to pursue any of those paths, so what we have now is an unclear future (in part because no one really knows if any of them will work).