Here are some answer to the question in the part "Overseas remittance without middlemen" - Where does the money exit? Cross-bolder payment+settlement trough c

Here are some answer to the question in the part "Overseas remittance without middlemen" - Where does the money exit? Cross-bolder payment+settlement trough crypto needs an bridge asset in the middle that would be crypto. So the in and out (exit) is done on either side trough a local cryptocurrency exchange or a liquidity provider potentially even a decentralize liquidity pool. But AFAIK currently its only done with normal exchanges. This means both sides could use fiat and theoretically do not need to know that the "money" went trough crypto at all. However there are ofc many people who do it manually i.e. they buy crypto send it to their families and explained to them how they can sell it. - Again, the transaction fees. Western Union is expensive; is Bitcoin or Ethereum doing any better.... Short answer, No. Both BTC and ETH are way too expensive (for typical low value transactions). PoW/PoS can not be cheap to transact because there is always a middleman taking a cut (fee). However there are other systems based on FBA (Federated Byzantine Agreement) which are specifically made to not have a middleman that collects fees. This results in transaction cost of fractions of cents regardless of transaction value and a settlement time of a few seconds. Note that the "cost" can not be zero to prevent spam but that money doesn't go to anyone so no one could have an incentive to raise the cost. Instead the cost adjust to network load so its cheap for everyone who does not spam. - Novel criminal potential. I dont think this will be a problem for commercial implementations of crypto remittance. Companies use some form of risk management with insurance and all that doesn't change much. The actual part where cryoto is involved is probably the easiest to secure (assuming the system explained above is uses and end user never "touch" crypto unless they choose to) For people dong it manually criminal do pose a risk but is it really larger than sending paper money via mail and then potentially take it to a bank to exchange it (yes people are forced to do this). Is it a particularly interesting problem? Probably not for most people but its large, like really really large. Several hundred billion per year and growing 5-10% annually. Million of people affected. Low risk for the target people, they are not encouraged to hold highly volatile assets or use them to pay for something.