I reckon that the average Incognito user is not even aware of "tracking" in the cookie/advertising way, and it's not why they use the mode. It's merely to not leave traces of their browsing history on their computer, which they may share with others.

To tech-savvy users it was always clear that sites would still be able to track you, whether or not you clear your local history and cookies. Cookies are just one, quite outdated at this point, way of tracking.