The threat is a necessary element of the crime. To convict somebody of extortion or blackmail you have to prove that the threat occurred, and that the accused intended to make the threat (which is slightly different in the case of extortion via intimidation rather than threat). Extortion is not a strict liability crime, and the interpretation you've provided doesn't account for the mens rea requirement. If your interpretation was true, then extortion or blackmail would just be a feeling that anybody could have at any time.
Yes my wording was incomplete. It requires intent, just causing the connection is not enough. What I wanted to say is that it's hard not to leave evidence of one's intent. And be it circumstantial. So while I'm sure a lot of blackmail happens with most cases never reaching the courts, I'm also sure that even people who are smart about it run the risk of a conviction.
But you still need an actual threat, not just a theory that a person intended for a threat to be implied. If everybody understands the potential consequences of not complying, then a threat isn’t necessarily required.
Now I wonder how common cases are where the threat is made in such an abstract way that it wouldn't qualify for a court. Because from the victims perspective, just acting on a highly abstract threat is difficult. You'd expect some bartering and a deal, no? The victim will need some kind of trust that their action will cause inaction on the perpetrators part.
You're still alluding to the use of a threat, which isn't necessary. If somebody knows that another person "has some dirt on them", then any demands that person makes are going to be evaluated in that context, especially if those demands are plainly unreasonable.
