The guidelines you linked state: "These Guidelines do not address the circumstances under which a processing operation may fall within the exemptions from the consent requirement provided for by the ePD".

Let's check what "Opinion 04/2012 on Cookie Consent Exemption" [0] says under section 3.6:

"""

3.6 UI customization cookies

User interface customization cookies are used to store a user’s preference regarding a service across web pages and not linked to other persistent identifiers such as a username. They are only set if the user has explicitly requested the service to remember a certain piece of information, for example, by clicking on a button or ticking a box.

...

These customization functionalities are thus explicitly enabled by the user of an information society service (e.g. by clicking on button or ticking a box) although in the absence of additional information the intention of the user could not be interpreted as a preference to remember that choice for longer than a browser session (or no more than a few additional hours). As such only session (or short term) cookies storing such information are exempted under CRITERION B. The addition of additional information in a prominent location (e.g. “uses cookies” written next to the flag) would constitute sufficient information for valid consent to remember the user’s preference for a longer duration, negating the requirement to apply an exemption in this case.

"""

See that you need to provide provide "information in a prominent location (e.g. “uses cookies” written next to the flag)" to be able to store user preferences in persistent cookies. You don't need consent banner for that (which I didn't say you need), but you need to clearly inform the user. The act of setting a preference together with clear information about persistence counts as a valid consent.

[0] https://ec.europa.eu/justice/article-29/documentation/opinio...