> even to know whether they've visited the site before
So uh, don't do that.
You don't need to notify if you use cookies for required functionality like login sessions or remembering a functional setting.
If you're tracking whether they're returning or not your activity is exactly the kind of behaviour the rule is covering because, in legal terms, it's skeezy as fuck.
It's a site where they log in and we store a cookie.
"Strictly necessary cookies — These cookies are essential for you to browse the website and use its features, such as accessing secure areas of the site. Cookies that allow web shops to hold your items in your cart while you are shopping online are an example of strictly necessary cookies. These cookies will generally be first-party session cookies. While it is not required to obtain consent for these cookies, what they do and why they are necessary should be explained to the user."
https://gdpr.eu/cookies/
Right, and then the legal teams tell me they don't care, and we should put up the cookie banner anyway. I feel like you didn't read my original comment.
That just means your legal team is lazy or incompetent. I work for a massive company that handles extremely sensitive PII and we don't have a cookie banner, because we don't need to have a cookie banner. GitHub doesn't have one, Gitlab doesn't have one.
> You don't need to notify if you use cookies for required functionality like login sessions or remembering a functional setting
Nobody wants to be the EU test case on precisely how "required functionality" is defined. Regardless of what the plaintext of the law says, it should be self-evident that companies will be more conservative than that, especially when the cost is as low as adding one cooke banner and tracking one preference.