> On a company/product website you should still inform users about them for the sake of compliance

No? Github for example doesn't have a cookie banner. If you wanna be informative you can disclose which cookies you're setting, but if they're not used for tracking purposes you don't have to disclose anything.

Also, again, it's not a "cookie" banner, it's a consent banner. The law says nothing about the storage mechanism as it's irrelevant, they list cookies twice as examples of storage mechanisms (and list a few others like localStorage).