To me the most obvious example of the failure of crypto is that nobody in Russia, at a reasonable scale, is using it to evade sanctions. I haven't even heard crypto-advocates explain why this isn't happening.

I hear all these anecdotes about people sending money back to countries in South America, but these clearly are happening at a small scale and with whatever crypto currency being seen as a slightly more complicated version of other money sending apps.

If crypto had a value prop to justify the absurd prices it would be that it would one day replace, or at least compete with, USD as a global currency. The fact that we aren't seeing articles about Russian oligarchs making massive financial transactions using crypto tells me that this will never happen. If ruthless billionaires don't see crypto as a viable means of evading sanctions right now, I can't imagine what conditions would actually make cryptocurrencies succeed.

Of course this brings up the obvious problem with crypto: do you really want to live in that world? For all the positive messaging around decentralized exchange, and anti-government rhetoric involving crypto, the reality isn't that it will be used by radical lovers of freedom to evade oppressive governments, but rather that things like sanctions will be impossible.

Either way, if crypto was going to become a serious player in facilitating financial transactions we would absolutely be seeing it right now. Since we're not, I'm not sure what arguments are left as far as the "you just wait and see!" crypto camp.