In this article it says with respect to:
Google Analytics and GDPR consent to cookies and tracking:
Based on a true choice. The user must be able to opt out of all but the strictly necessary cookies and still use the site. Retrievable. The user must have access to their settings and make changes to what cookies they want to accept and reject.
Is it the responsibility of the site to implement this or is this something that the user should be able to do via the browser?