So a TAM of money launderers and people without money. Do you see why these "use cases" are laughable?
You didn't replace the bank. You just created a worse version of it that works for a small segment of the population. A segment which happens to be highly uneconomical to service.
There are still many unbanked people in the world. I don’t think it’s a laughable use case to want to bring those that are too poor to participate in the banking system into the modern era. See Humaniq for an example of this.
I don't either. But something like M-PESA, which works (a) without a bank, (b) on cheap hardware and (c) without requiring great technical knowledge to avoid your coins getting stolen is a better fit for that problem.
The regions with widespread poverty aren't going to be enthusiastic about the fees, and wild instability that comes with crypto database tokens, Ethereum and so on.
The real use case is obviously money laundering, but everyone wants to try to spin the marketing into unrealistic areas.