Unfortunately events like the ones we've just had are what's necessary to demonstrate to people that no, we actually do need technology like this.

Cashless is going to happen. The convenience gain is too large for it not to. Cryptocurrency is the only way to preserve any semblance of genuine sovereignty in a cashless world. It is a technological necessity.

HN's bias against cryptocurrency is a useful counterweight to the massive profit-motivated hype surrounding it.

Most cryptocurrencies (including Bitcoin and Ethereum) do not solve this issue, governments could order businesses (or payment systems used by businesses) not to accept payment coming from some blacklisted addresses, even indirectly; and this is possible thanks to the public ledger.

And they could outlaw any cryptocurrency that does provide anonymity for senders (Monero, GNU Taler, ...). While easy to bypass for individuals, legitimate businesses would not. Governments might even ban cash one day.

This is a social and political problem, technology won't solve it.

It still blows my mind how antagonistic HN is to cryptocurrency, particularly Bitcoin.