A fundamental flaw in this, is it still involves user data, even if “anonymized”. You can advertise without any user data.
Right. The reassurance is supposed to be: "don't worry, no personalized data is retained." So, ideally, no individual record of you, with your likes, your behaviors, your browser fingerprint, aggregated together with whatever third party provider data might be purchased, and machine learning inferences can be derived from that. Instead, there's a layer of abstraction, or several layers. Like "people who watch Breaking Bad also like Parks and Rec and are 12% more likely to be first generation home buyers". Several abstracted identity types can be developed and refined.
Okay, but who ordered that? Why is that something that we think satisfies us that privacy is retained? You're still going to try and associate me with an abstract machine learned identity that, to your best efforts, closely approximates what you think I like and what is most persuasive to me. I don't think people who are interested in privacy feel reassured at anonymized repurposing of data.
It's the model itself, it's the incentives inherent in advertising as an economic model, at the end of the day. I don't know that there's a piecemeal negotiation that is supposed to stand in for our interests to reassure us, or whose idea was that this third way was going to be fine.
My guy.... you linked to a youtube documentary about the questionable economics of gold and a blog post about an unreliable certification group associated with Rainforest Alliance. Not because of anything specific to gold or certifications, but... to illustrate the general idea that corporations can be bad?
The level of generality you have to zoom out to, to associate those to Mozilla, is the same level of zooming out typically used for Qanon conspiracy theorizing.
This is exactly the kind of thing that people make fun of with Six Degrees of Kevin Bacon. If you're willing to zoom out to six degrees, you can connect Kevin Bacon to anyone in the history of cinema. It doesn't prove that Kevin Bacon is personally connected to everyone in the history of cinema, but what it does prove is the frivolousness of reasoning from such stretched out connections. That goes for historical connections, but also funding connections, and, perhaps most importantly here, for conceptual connections. And I would venture that trains of thought hinging on such remote connections are a hallmark of fuzzy thinking, which is why it's terrible to go from "Rainforest Alliance bad" to "... and therefore Mozilla ad privacy is bad."
That's not to say one shouldn't be concerned about Mozilla's venture into advertising, but that this is a terribly incoherent way of showing it, that's as liable to produce overextended false positives connecting anything to anything as it is to produce any insight.