So your position is that words can be illegal even if they aren't even intended to be followed up with action? Wow, that's a weak branch you're sitting on. Yelling "fire!" in a crowded theather would be illegal, but I don't see the Dem Senators' speech as rising to that level.
I think this is much more akin to someone saying, "You know, a lot of rich people keep money in that bank and there's not even a security guard." In your world, that would be enough to convict of conspiracy to rob a bank.
I disagree with your analogy. If I threaten to extort you for a million dollars if you don't do what I say, and you go to the cops with that information instead, I'm still guilty of extortion. If I threaten your ability to speak out against the government, even if you go ahead and speak, I'm still guilty of violating the First Amendment.
First of all we are not talking about mere "words", as if someone just wrote a string of meaningless words on a page.
Communicating a threat is not simply "words", the communication itself is a form of action. It is not germane if the person to whom the threat is made believes or does not believe the threat will be acted on. The person receiving the threat has no way and no requirement to know if the person making the threat intends that threat as a bluff of not. The intent to act or not is irrelevant to the law with regard to the act of communicating a threat.
Did the Dim Senate Leaders threaten Disney/ABC? Yes, by direct implication. Did they imply that they would take action against Disney/ABC if Disney/ABC did not give in to their threat? Yes. Was the cause of that threat the fact that Disney/ABC, exercising its free speech rights, was going to air something that portrayed an opinion that differed with the opinions of the Dims and they did not want the public to hear that opinion? Yes. Does any American public official have the right to abridge the free speech rights of someone, simply to abridge those rights for their own political benefit and due soley to political differences of opinion? No.
Second: The analogies you presented are not analogous to the exact particulars of the situation.