The standard "Accept Cookies" banner is, give or take, malicious compliance to the EU's cookie laws. For actually required things, it doesn't *need* to be a banner. Companies tend to use a standardized, third-party-powered "follow the EU law" tool that they get the ugly cookie banner. And even that banner's malicious compliance is under attack now because it takes too many steps to opt out.
For things like sign-in, you barely have to mention the use of cookies on your website, because it's necessary. For things like items in an anonymous shopping cart, a simple "adding this item to the cart when you're not logged in will cause the item to be saved in a cookie so we can remember it later" would suffice.
I'm not a lawyer, but that's my understanding.