Here is what the Norwegian Data Protection Authority says:
In the cases of Smaato, OpenX and AdColony, Grindr “only” transmitted a signal conveying the data subject’s “opt-out” preference. We understand that advertising partners could choose to ignore that signal. In any case, Grindr would have to rely on the action of others, either the user, the operating system, Grindr’s partners, or a combination of the aforementioned, to halt its sharing of data where so required. In consequence, Grindr failed to control and take responsibility for their own data sharing, and the “opt-out” mechanism is not necessarily effective.
Furthermore, for a consent to be “freely given”, accepting to the particular processing operation should be as easy as declining, and the choice should be intuitive and fair.
[1]: https://www.datatilsynet.no/en/news/2021/intention-to-issue-... ("Advance notification of an administrative fine")