Nope - 'decline' has to be the default assumption for GDPR compliance. You only need the banner if you want people to opt in.
The web of 2020 has become a hostile and ad infested place. I miss the simplicity of the 90s, but it might be nostalgia bias.
I giggle every time I find this dark pattern thinking it is the modern equivalent of the ballots for the Austrian Merging referendum of 1938 [1]
[1] https://en.wikipedia.org/wiki/1938_Austrian_Anschluss_refere...
For example https://www.telegraph.co.uk/ (right wing UK newspaper). In the pop-up it says "You can also review where our partners claim a legitimate interest to use your data and, should you wish, object to them doing so.".
If you click manage it opens with "user consent" selected, where everything is turned off. Click save means they're not going to start tracking you, right?
Wrong, if you switch to "legitimate purpose", you'll see that everything is turned on. All those ad companies claim they have a legitimate purpose to be tracking you, even though you have zero business relationship with them.
Unless the ICO hands out some very heavy fines to those companies, the whole thing's become a farce, just like the cookie law was.
GDPR enforcement is approximately zero, to my knowledge, so I don't know if there's even really an answer to the question.
For what it's worth, Wikipedia gives the impression no-one really knows. https://en.wikipedia.org/wiki/General_Data_Protection_Regula...
ICO, the UK regulator, seems to take a dim view of dark patterns, but they're only outright banned for children's content: https://ico.org.uk/for-organisations/guide-to-pecr/guidance-...
(PDF) Irish DPA's sweep of thirty-odd websites under its jurisdiction. Lots of good guidance here, but for the point specifically under discussion, ctrl+f "nudge." https://www.dataprotection.ie/sites/default/files/uploads/20... by the DPC on the use of cookies and other tracking technologies.pdf
(PDF) English translation of Greek DPA cookie guidance. See in particular the last page, "Bad Practices." https://iapp.org/media/pdf/resource_center/Greek_DPA_Cookie_...