If this was about Do Not Track headers, maybe. That’s a browser setting that Google describes in plain English, so expecting Google to follow it may be a credible expectation.

Incognito mode opens up a page that describes that websites will still track you for every new tab. I’m pretty sure this has been the norm ever since the feature first became part of browsers.

There are many things that Google does wrong and that they should be fined for. This is not one of them.