Earlier quoted context omitted.
Found the full lawsuit PDF https://www.insurancejournal.com/app/uploads/2020/06/brown-v... It looks like this is mainly about the fact that Google Analytics still works even if you are in Incognito mode.
Which there is a warning of every time you open an incognito window. It's not fine print either, it's one of about six bullet points. "Your activity might still be visible to ... Websites you visit." This one is going nowhere I suspect. Just because a lawsuit asks for big damages does not mean the plaintiffs are likely to prevail on their claims.
Maybe instead calling it "incognito mode", which is totally inadequate, they should call it "temporarily disable browsing history" instead.