Re: Should result in summary judgement...
That's well-established, not just GDPR. It's explicit in GDPR, and lawyers like "explicit", but if you didn't have something like that it would be a breach for somebody to put your name and address on a letter they post to you. I've had GDPR opt-in emails warning me that I won't get any notifications of dispatch if I don't opt-in. Which means they're saying they can't fulfil a contract. without an opt-in to everything.
How dodgy is that? A US service gave me a web page with default-on permissions for over 300 companies they share my data with. I tried to count them, as I clicked to "off", but lost track at over 270. As the Good Book says:
"Three shall be the number thou shalt count, and the number of the counting shall be three. Four shalt thou not count, neither count thou two, excepting that thou then proceed to three. Five is right out."