Ah, yes, the ends justify the means, Dr. Mengele

How is that any different than what all those shady companies do?

Manipulation only really works so far as it's actually grounded in something. Like, sure, that sounds epic and evil and a machiavillanous type of thing, but it's usually just easier straight up to actually come up with a compelling argument that "manipulates" people into seeing it from a real angle, than to have to try to do backflips in order to come up with some totally fake argument that isn't real but also appeals to them specifically and slots into their worldview and directs them where you want them to go. It's easier just to start with the reality of the situation and your authentic belief and then come up with a package for that which they will find acceptable.

At that point, where you're actually basing your argument in something, "manipulation" becomes "framing". We move from a false construction, to just selling a new angle on the reality. Maybe that's the same thing, to you, but there's definitely a meaningful difference there.

In this case, the false construction is the idea that data is similar to property, and you need to own your property rather than give it away. Sure, this might push people in the right direction, but they're also just as likely to find it acceptable to trade their property for a service (as is what these social media companies do, if the metaphor was extended), or to sell their property for a return in a more straight kind of way.

Then you start getting into problematic ideals where people prize their art for its economic returns and hate AI (or stable diffusion) for "stealing" from them. For "stealing" their "intellectual property", and for stealing potential economic value they could've extracted out of that. This, rather than hating it for being a huge investor level scam, that tarnishes the core technology's viability, for being massive undirected energy drain, and for enabling mass internet botting more than what we already had.

It's better to deconstruct the idea of intellectual property, while also advocating for user privacy as a kind of right that exists, and actually gives something or does something useful to those which have it, those which have real privacy. Selling it as something good for the individual, to the individualist, selling it as good for society, to the collectivist.

Beyond that, if you're arguing against someone who believes in the market, and in this sort of meritocratic lassiez-faire intellectual utopian cyberspace ideal, then that's the real core of the issue you must solve, rather than getting into this privacy/intellectual property debate, where it's impossible to really change their minds because their core values are incompatible with the idea itself.