what business is it of lauda to run a sting operation
is lauda the police ?
why should lauda care if he paid his taxes on his crypto ?
From what I've read, that whole thing wasn't ultimately about taxes and the signed message from Lauda prior to the operation explains what they were doing. It was ill-advised for them to do that, especially as Lauda was a staff member at the time, and he/she even admits that. I think that's also why Lauda got removed as a staff member, but I did not see this as a true extortion attempt, especially coming from Quickseller. Those two have been feuding since forever.
As far as the harassment goes, that's an assertion that I've never seen evidence for. I'd tend to agree that threatening via telephone is a really bad idea, but I don't think I have all the facts to make a judgement on that. I don't know what was said or if any such phone call was ever made. I don't even really understand what the whole sting operation was supposed to be about other than the suspicion that zeroxal was involved in some criminal activity.
That is a ridiculous assertion on both fronts. I challenge you to find someone who has claimed I have stolen or misappropriated funds (that is not later shown to be baseless) -- I will save you the time, no such claim exists. (I await your apology when you agree no such claim exists).
Of course the whole "sting operation" was not ultimately about taxes. It was about the fact someone was known to have a large amount of bitcoin worth hundreds of thousands of dollars and few living expenses. Paying any extortion bounty is not even evidence of wrongdoing, it is evidence the stopping of the threatened criminal harassment and probable hassle of an IRS audit is worth more than value of the bounty.
The signed message was also not a signed message, it was the claimed content of an encrypted message (lauda knew the difference at the time) that was posted to multiple pastebin websites in order to create the appearance of an alibi if/when he was called out on the extortion attempt. It would be impossible to ever see the "signed message" if it was not presented and decrypted. If the extortion bounty was paid, it is almost a certainty lauda would not have been called out on the extortion, and there would be no reason to ever present that "signed message". There could even be more "signed messages" out that that are similarly encrypted that say something different that would be presented if the extortion was paid and lauda was called out -- we can never know one way or another.