Cookie consent banners are a joke. The real thread lies elsewhere
Cookie consent banners aren't just annoying and (according to the GDPR) unnecessary as long as no external trackers are used. They also distract from the the fact that the underlying issue, user tracking, has long since moved beyond the web and festered.
I’m not particularly worried about tracking cookies on websites. Those were always easy to manage without a lot of trouble. If you are using Firefox, just configure the browser to throw away cookie on exit under ☰Edit > Preferences > Privacy & Security. That takes care of it, at least on the desktop.
The real problem, though is, as usual, mobile, Android in particular. Here you don’t have to deal with just one, but (at least) two system level supercookies, you are neither warned, nor can get rid of:
Ad ID
Google Services Framework ID
The GSF ID is issued to your phone when you first bind a Google account to it and stays valid till the next factory reset. It is a unique 64 bit identifier that is always transmitted (X-DFE-Device-Id HTTP Header) when the device talks to Play. There is no way to opt out of this. No GSF ID simply means no service. The thing to keep in mind here is that while the GSF ID is private to the Google Play app, that app also defines a vast number of background services, which often perform tasks on behalf of other (third party) apps. So even if you don’t actively browse the store, you can count on your GSF ID being transmitted every couple of minutes.