Incognito mode does exactly one useful thing: it prevents the browser on the machine in front of you from saving your history, cookies, and form data after you close the window. Consider what Incognito does not hide. It doesn’t matter whether your browser is in private mode or not — the DNS lookup happens at the operating system level, well below anything the browser controls. Incognito mode, by design, does not touch fingerprinting. I’m not arguing that Incognito mode should be removed.