It's technically stupid in the first place.

It's YOUR browser, a locally running software on a physical computer YOU own which memorize the cookie key-value pair a remote host told YOU to memorize and YOU return the same value later. It's YOU who allowed the cookie. If YOU don't want to allow the cookie, YOU simply not allow it.

You are technically 100% control on cookie. These JavaScript implemented in-page UI has no guarantee to respect your wish. But you have a power to disable it.

"Cookie banner" is a colloquial name; not a technically accurate description of what the banners are for.

GDPR is not about cookies; it is about tracking. Whether the tracking is done through cookies or through other means makes absolutely no difference.

You can prevent some tracking via your browser, but definitely not all of it.

It's not quite the same thing since the same cookie used for login (doesn't require consent) could be used for tracking (requires consent). But also, basically nobody cares.

This has nothing to do with cookies, and everything with pervasive and evasive tracking.

E.g. storing your precise geolocation for 12 years: https://x.com/dmitriid/status/1817122117093056541