If you're in incognito mode and you visit a website with an embedded Facebook Like button, and Facebook's Javascript uses browser fingerprinting[1] to track you and build a further profile of you, do you expect that entity to not know who you are just because they don't have access to their usual cookies?

[1] https://blog.mozilla.org/internetcitizen/2018/07/26/this-is-...

Wouldn't the same be true with any other browser's incognito? What does this have to do with Chrome? The irony is that to do what these people ask for (Analytics somehow not tracking you in incognito), they would have to actually add in a way for Analytics to detect you are in incognito.

No, because I directly interacted with those entities. That's different from Google Analytics, where an entity with which I directly interact informs a third party unbeknownst to me.

No need to explain any different. The solution is to simply not track the user on websites, which they own, when the user uses incognito mode. That would be the honest way, but it will never happen, because then other browsers could try to pretend, that they are incognito Chrome.

So that leaves us with "do not trust privacy protection of an ad company".

A reasonable expectation would be that Amazon doesn't know about the Facebook post, that Facebook not know about the Times subscription... etc.

Replace the left side of the expression with "Google" and you'd have what most users might expect from Incognito. That is, that Google not know about the Amazon purchase, Facebook post, or Times subscription. That Google does know, essentially, even from Incognito, is the problem.

But Google doesn't know who you are when you're in incognito. They famously "don't do fingerprinting".

Of course, if Amazon or Facebook or the Times tell Google or at least hire someone to figure out who you are and tell Google then it's surely not Google who is tracking you.

And likewise, if Google Tag Manager and Google DoubleClick Ads make it easy to add and integrate with the one or two missing pieces from third parties to make this work, then it's not Google's fault either.

Why do you think Google knows about the Amazon purchase or the Facebook post? They don't.

I was sticking with the analogy established in the post I was replying to. To me they are variables in the pseudo-code, for the purpose of understanding the algorithm, not the actual underlying reality being discussed.

Right, but GP picked those variables intentionally, as things that Google doesn't (can't) track. If, for example you replaced "Amazon" with "Google", well you'd obviously expect Google to have the data.

So then if you replace "Amazon" with "company that subcontracts to Google for analytics", you'd still expect Google to have the data.