They can leave, sure. I don't think they have a right to "threaten" anyone, and they certainly don't have a right to strike, not being in a union or even trying to form a union.

They could however form a union first and demand a labor contract in which every Netflix employee has the right to veto content shown on Netflix. Then they could go on strike if the union fails to agree on a contract, saying that this "right to deplatform" is a non-negotiable demand.

That is the equivalent of what is going on here, which should explain why the rest of the world thinks this is a terrible idea. Anyways, good luck with that.

> I don't think they have a right to "threaten" anyone

Of course they do. As a worker, I have a right to threaten to quit during a negotiation process. As a consumer, I have a right to threaten to cancel a subscription or stop buying a product. I'm not sure where anyone would get the idea that those kinds of actions aren't allowed in a free market.

> and they certainly don't have a right to strike, not being in a union or even trying to form a union.

I also really don't understand what's meant by "right to strike" here. I'm not aware of any strike laws in the US that ban employees of entertainment companies from striking. Without a union, Netflix workers can't call an official strike, but they can still legally refuse to work, and Netflix can respond as it sees fit.

If they don't have a right to do what they're doing, then Netflix can try pressing legal charges against them or at the least can fire them.