TL;DR: Propaganda and consumerist traps function when they appeal to a core value of the receiver.
Re: spoiler culture. Both side are correct. I know, I am a big brain special genius. To be honest, I never like the "well the truth is somewhere in the middle" assumption, the golden mean fallacy, so I'm always dissapointed in myself when my actual opinion on a topic boils down to that.
What I will say is that consumerist traps work because it appeals to peoples inclination. An exemple of this is propaganda. There used to be this idea of the "hypodermic needle" model of communication, which stated that viewers will just uncritically absorb information given by media. Turns out, it is not true, or at least not as true as we thought. I think to be influenced by media, you have to allow yourself to be influenced, or at least be ok with it influencing you, and one way propaganda create that state of mind is by appealing to values a part of the population will relate with.
Now, spoiler culture is not propaganda. Rather, I was using this example two explain how these two truths can be reconciled: 1) spoiler culture is a marketing creation to affect how users engage with the product and 2) some people genuinely prefer when they don't know the twists and turns of a story. People in marketing appeal to 2) to create 1).
So the next question is, could this be done differently? Could there be a new kind of spoiler culture? Personally, I'm kind of mid on the whole thing, sometimes learning the twists of a story will make me want to watch it, other times I will make some effort to avoid spoilers (but not that much effort, and if I get spoiled, it's ok). That being said, it's not like its a critical issue, like of all the consumerist trap, it's not one that ruin society, at least I don't think.