A buyer should be as much as possible anonymous, but a seller should not

GNU Taler is a payment system built on this philosophy

if the developer was unaware of this risk, they were very naive

Well, their security audit didn't seem spot the risk...

Seriously, though, are you condoning someone being arrested for publishing software?

getting your work used by criminals shouldnt make you a criminal though.

except sometimes its not used for purchasing and sometimes used for donations i.e. donations for Ukraine were done through eth and people (including vitalik buterin) used Tornado Cash to donate to people\organizations without it get traced to vitalik and the user\org

So if someone works on software for cars and they’re used to run people over the responsibility is on them? Seems like a terrible way to go about it.

With that perspective tim berners lee has aided so much terrorism, money laundering, and blackmail by coding the world wide web. Or Protonmail coders or apple cosers for making end to end encryption simple to use

ok then does that apply to software that makes it easier to obfuscate communication? people can use it to plot terror attacks, or send grandmas secret recipe. people can use tornado cash for money laundering, or for hiding how much money you have and where your spending it from an abusive ex or authoritarian government who might target you for paying for an abortion

Same argument to be used to lock up anyone who's ever contributed to a torrenting app or to the protocol itself.

Whatever your opinion on crypto, taking it down might have some acceptable reasoning behind, but going as far as to arrest the developer is extremely concerning.

What are you even talking about? It's 100 percent a question of perspective because as I hope you know, this argument is used constantly (copying files is or should be illegal).

The fact that you consider it to be a "real crime" should be more than enough for you to realise it's a ridiculous position.

Personally, I don't consider keeping your financial transactions secrets to be a real crime, regardless of what method you're using. Now what?

Good job, then people will just use Monero instead. Private by default and no need for mixers.

Would it change your opinion if he was paid for working on the software by the criminals?

Yes, it would change my armchair not-a-lawyer-but-i-play-one-online legal opinion. If there is evidence that he was (knowingly) hired to write the software by people who were planning to violate laws using the software, then it is not as much of an open-and-shut first amendment case (assuming they're planning to extradite him to the US...).

It is currently unknown and given the nature of the software involved might never be known

Indeed. Which is why your assessment of his arrest should not be based on the assumption that that is what happened.

This is just another example of how the government overreaching and trying to control our lives and stifle creativity and innovation. The developer should be applauded for his work, not persecuted by the authorities. By the way, Tornado Cash Still works on IPFS