You can't look at it in a binary way. Of course it's a bad idea to prescribe people their needs. I wouldn't want someone telling me what I am to have for dinner. But there are also needs that are obviously better left unmet. For instance I may feel a need to take possession of your property. It's not a kind of freedom you'd want to grant to me.
I think it is rather binary, but I think your example in this case demonstrates a different principle.
Having my "needs" defined separately from my "wants" denies me my freedom. But that's different from you say, deciding to confiscate my things without due process.
> I'm terrified of others prescribing what's "needed" because someone else has decided what what's "wanted" isn't the best for them.
I'm equally terrified of others convincing you that what they have to offer is the best for you, with minor tweaks to "cover your needs"; yet that's the basis of profit-based marketing.
I respect your concern (I'm trying to be non-specific in terms of pronouns here, but it's hard), but that's a fear we have to live with, no? The notion that someone else's argument might be more persuasive than our own, that someone else's message might be accepted instead. Surely, there's something perverse about it, underhanded, or perhaps I'm just not enlightened enough, otherwise I wouldn't accept such a false pretense. Surely, if I'd been shown the light, and not doused in such propaganda, I'd make a better choice!
The problem with that of course, is that a lot of people can make that argument. And regardless of who's making the argument, be they weak or strong, they all rely on the premise that the person needs convincing of something, because to imagine that they might come to a conclusion that's not your own /by themselves/ is a terrifying thought.
I'm sorry, but I really can't condone the notion that some messages should be feared in that way, and that someone else knows what's best because they presume I do not.
I'm terrified of others prescribing what's "needed" because someone else has decided what what's "wanted" isn't the best for them.
That's no freedom at all.