How so cryptocurrencies haven't solved anything? If someone has done a transaction with cryptocurrencies that brings value to him, isn't that solving something? Your claim is just very probably totally untrue - I think Bitcoin etc have been very useful for some small group of people for quite a long time already. However the adoption just isn't that big. Somehow people seem to think that cryptocurrencies have to replace the existing financial system to be useful. Meanwhile they can be just be used by 100 people worldwide and still be useful.
Cryptocurrencies accomplish nothing that wasn't already possible before, usually faster, cheaper and safer. Just because someone uses an alternative doesn't mean it's solving a problem, and in this case it's just creating more issues.
I have used Bitcoin to buy various things and used it as a savings instrument, I see that it has solved problems for me. Of course I could use other tools for that, but if you think Linux is superior that doesn't invalidate someones experience who is using Windows.
Generally there seems to be lots of people who don't use cryptocurrencies and think that they don't solve any problems - OK whatever, don't use them, but there are loads of people using cryptocurrencies for whatever and your opinions are not objective measure on their value.
