> How about real time cross border remittance and settlement? Current fiat approaches require large illiquid reserves, are slow, and not very scalable.
It's bad for that, we've been through this. To send money you have to pay ~1% to an exchange in your home country, wait a few days for it to clear exposing yourself to huge forex risk, pay a $1 transaction fee give or take, then pay ~1% to an exchange in your destination country netting you 3-5 days latency, 2% fee plus $1 plus 10 minutes and incalculable forex risk. And the risk your exchange will literally just steal your money a la Quadriga. Or getting it confiscated en route like the $825M taken from Bitfinex by various government entities for laundering money.
There are a lot of solutions to this problem ranging from a credit card to buy things, TransferWise (0.85% fee give or take) to Interactive Brokers ($20 per million fee, or 0.002%) to Norbert's Gambit (free) to a wire transfer if you have to settle instantly. Or even just opening an HSBC account in both countries and moving the money instantly online via web banking.
Then there's Square Cash and Venmo for free domestic transfers, the free/instant domestic RTP network in the US, the free/instant SEPA network in Europe and the often free/instant Interac e-Transfer network in Canada.
> ...and not very scalable.
According to the Bank for International Settlements triennial report of 2016, the foreign exchange market cap averaged $5.1 trillion per day.
That's $1,861.5 trillion dollars per year. Forgive me for thinking that means the scaling issue is pretty much solved. It's probably the single most liquid market in the history of the world.
> It’s also useful for transmitting money long distances when banks won’t do business and you want to avoid a paper trail (drugs).
I did say a legal use case. One that neither violates laws nor sanctions. Worse, Bitcoin leaves you with a paper trail. You'd have to use Zcash or Monero.
> Fiat is perfectly fine for in person transactions, but not when distance is involved. You may or may not morally agree with it, but this is a proven use case.
It is, though, because you can use your Visa card to send money instantly to anywhere in the world that isn't sanctioned.