I try not to intrude into the conformitygate space. For the most part, it's harmless theorizing. But there is one thing I can't ignore anymore.
There is no long con, no master plan, no deception. Stranger Things is over. The spinoff is nothing more than a cash grab. It's not part of some plot by the Duffers to fool the audience.
The Duffers aren't even involved anymore. They've moved on to their next projects (which I urge people to ignore). They aren't even working with Netflix anymore for these new projects. Netflix owns the rights to the Stranger Things property now. The Duffers do seem to have retained Executive Producer credits, likely as part of the deal that granted Netflix the rights, but it likely doesn't mean anything. They may technically have final say, but most likely in a "rubber stamp" sort of way.
There's no hidden message from the cast. Yes, they say some seemingly scripted things about the show, but that's all part of their contracts. They're not allowed to actually speak their minds, whether they liked the show or not. They can only say what they're told to say. Even if their contracts are up or don't cover that, they'd still be expected to say positive things for the sake of professionalism. Even when Noah said critical things, he was still very careful about how because he knows he can't explicitly say anything bad.
The social media and marketing teams aren't up to anything. They're just pushing the spinoff. The marketing has always been a bit fourth wall breaking. In the lead up to season 4, they pulled stunts where the Upside Down was creeping into the real world. It's all just an attempt at immersion since the show relied on the idea that there's this shadow reality trying to get into our world. Of course, the Duffers went and destroyed that mystique by revealing it was all, somehow, just a wormhole.
I'm sorry that it ended the way it did. I hated it, too. I also believed that it was all a fake out at first. But nobody would sink their own project and risk losing everything all for the sake of a swerve months later, and no investor would ever go in for that.
So, by all means, theorize. You come up with ideas that are leagues better than anything the Duffers proved they could manage. But, please, move on from the idea that it's all leading up to something. The Duffers don't deserve it.