Between the speculative get-rich-quick rollercoaster of Bitcoin and the fraud of other crypto currencies it feels like the promise of decentralization has been forgotten.

That's just shifting the problem one inconvenience further. How do you purchase cryptocurrencies without Visa/MasterCard/PayPal?

I'm not sure what options they have, but ideally, for convenience some kind of local country bank transfer, which could be to a local crypto dealer. That might take days but you might "stock up" on crypto to compensate.

Or peer to peer cash/crypto swap might be required.

Or businesses themselves sell some of their services with crypto.