The same argument could apply to firearms (shouldn't harm the holder, so the same firearm model shouldn't hurt other holders of the same firearm model?) and a lot of things.
Google's fundamental business model involves tracking people, so if you use one of their features that supposedly turns off tracking, it would be natural to assume that Google would stop all tracking.
The internet was not designed to track us. Unfortunately, we've allowed it to happen.
That doesn't mean they can't track you when you steal something. You are not unidentifiable.
I go out of my way not to use suggestive names like incognito because for the non-technical, it creates an expectation that will be relied upon by those that do not have the background understand what they are reading. "History-less", "local self-clean", "non-caching"... All of these names are accurate and far less suggestive than incognito. Incognito, like it or not, evokes the expectation that the browser is doing something to frustrate monitoring by other parties.
Here be the wrath of the non-technical masses, and why the "luser" attitude is the most destructive, anti-social, and regressive attitude in tech.
Our goal should be simplification of computing. Not the unceasing obfuscation and complexifying of it in some misguided attempt to create job security. I sincerely hope Google loses. Hard. It's about damn time that the tech industry be held to a higher standard.
Google needed a name that fits on a button, translates easily and is recognisable. That's why we're using "browsers" instead of "HTML5 user agents", why we use "windows" instead of "top level control elements" and "sleep mode" instead of "ACPI power state S3". Using technically correct terms for the general public is exactly why people prefer dumbed down smartphones over complex traditional software.
Since its inception, private mode has shown a screen that describes what it does or doesn't do whenever you open it. Had Google omitted that, and directed private mode directly to the user's home page, then perhaps I'd agree with you. In this case, I believe Google did the best they could to balance a technically correct explanation with something that's understandable by normal people and children.
You can't blame everything on "the user shouldn't have to know better". An automatic gearbox won't put itself into reverse when you want it, but it's still called automatic. A juicer won't turn a spoon into metal juice. A vacuum cleaner won't work in a vacuum. All of this is perfectly logical if you're used to the context things are used in, but that context obviously doesn't need to be part of most products' naming.
Misunderstanding naming and terminology is a sign that things need better explanations, but not the basis for a lawsuit in my opinion.
And it does this: cookies are not shared or stored past the session, etc.
The issue is that some tracking can still be accomplished by websites, even while other tracking is stymied.
What do you call this?
IIRC, this was not considered a bug.
If you aren’t technical and understand difference between client and server, you may not know that while using one Google product, that claims to be incognito, other Google products are still tracking you. That’s how internet is designed to work, but when one company controls clients and servers, it can get confusing to a general public.