I wasted years of my life in crypto

The problem with this argument is that cryptocurrency now exists whether it's legal or not and using it for illegal things is already illegal. Drug dealers are committing a felony by selling drugs and if that hasn't deterred them then neither will making something else they're doing a crime too.

So all of the negative uses are going to happen regardless of whether you also ban the positive uses. At which point, what are you gaining by making it illegal or inconvenient for innocent people to use it for something that isn't otherwise illegal?

> Since blockchain is public, you can always trace "bad" or real bad payment to the source wallet. That i one issue, and another is that since BTCs are non-fungible, the tokens used in such payments are forever tainted.

People keep making this claim and it keeps not making sense.

You don't need someone's permission to send them Bitcoin. Meanwhile large exchanges keep billions of dollars in a single wallet and have single wallets that do billions of dollars in transactions over a short period of time.

So let's consider the two possible ways this can work: First, if you get coins directly from a tainted wallet then you get in trouble, but if it was several steps back then it doesn't matter. This is, of course, useless, because then people would just transfer the coins through a couple of other wallets first.

Second, any wallets that receive any tainted coins become tainted forever. Then immediately the vast majority of the chain is tainted because the coins have made the rounds through a large exchange at some point. Worse, it's pointless to try to defend against it by refusing tainted funds, because you can't actually refuse funds. Your billion dollar wallet or freshly mined Bitcoin can be tainted by any troll who sends you a dollar from a tainted wallet without your permission, and trying to treat coins as non-fungible is probably a good way to get someone to troll you like that.

Which gives you two alternatives again. The first is that all coins can be tainted by trolls, which will in practice cause exactly that to happen and thereby make the premise meaningless. The second is that you can try to say that it doesn't count if someone sent them without your permission, but now you can't tell if something is tainted by looking at the chain because it can't tell you which transactions were unauthorized by the recipient, and moreover you would then have a mechanism for getting dirty coins into a clean wallet.

In other words, when anyone can send you money without your permission, your options are "everything is dirty" or "everything is clean".

> Finally, assuming that the parties are rational agents and the smart contract language is Turing complete, we argue that it is impossible to implement the basic sales escrow as a smart contract without trusted third-parties or vulnerability to extortion. In other words, any escrow smart contract has one of the following three demerits:

> – Assuming irrational agents who are willing to punish the other side, even if it is not in their own interest; or

> – Relying on a third-party; or

> – Enabling at least one of the two parties to extort the other.

> In summary, we illustrate that the smart contract and Dapp community is wrong in assuming that the current implementations of two-party escrows have a well-designed mechanism that incentivizes rational actors to be truthful. More shockingly, we show that the smart contracts on programmable blockchains have inherent limitations that make it impossible to implement such a contract. In a sense, this can be considered the first incontractability result on programmable blockchains.

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This is exactly what I was arguing.

I never claimed that two party escrow is ideal. I was explicitly saying that two party escrow is an intractable problem and that you must formalise your trust assumptions instead and either accept some level of trusted third parties OR without third parties accept some level of risk of exploitation by one party or the other. Even with third parties there is still risk for exploitation but depending how it is implemented that risk is lesser.

Again this is a matter of formalising trust assumptions and explicitly outlining who you are trusting, what you are trusting them to do, and how much you trust them to do it. And in doing so up front both parties can evaluate their risk tolerance based on the agreed upon contract before progressing.