This is pretty much a follow-up to this meta announcement by SE. Ideally that announcement would have resolved the issue, but the language in it was vague and evasive, and there have been no clarifications by SE in the 2.5 weeks since it was posted.

The trigger for this issue was a report that one of the ads on SO was trying to start an audio context in the browser. One of the answers shows that the main purpose of the suspect script is to fingerprint the browser. I looked a bit at that script myself, and that ad contains a ~80 kB minified Javascript file that really looks like the only purpose of it is to query all kinds of obscure details about the environment, and I can't see any other purpose for this except tracking users without the restrictions cookies or other systems impose.

The original response from Stack Exchange was the following:

We are aware of it. We are not okay with it.

This is still there on the original post and not retracted. The later meta post by SE paints an entirely different picture. It is evasive and in my opinion missing the point entirely. The Stack Exchange response claims that no PII is collected, which is really not what this is about. Fingerpinting is about being able to track a user across sites without the browser security getting in the way, identifying the user is a separate process. You don't have to collect PII to fingerprint users, but it's still a very invasive thing to do with a drastic effect on the privacy of users.

The Stack Exchange response also claims that the ads comply with some advertisments standards and other regulations. As far as I can tell this is simply repeating the claims of the ad tech provider. But it's also avoiding the original question, are those ads fingerprinting Stack Exchange users and tracking them across sites?

So I'll request a response from SE on the following questions specifically to clarify the, at least to me confusing previous response: