"(42) Where processing is based on the data subject's consent, the controller should be able to demonstrate that the data subject has given consent to the processing operation. [...] For consent to be informed, the data subject should be aware at least of the identity of the controller and the purposes of the processing for which the personal data are intended. Consent should not be regarded as freely given if the data subject has no genuine or free choice or is unable to refuse or withdraw consent without detriment."
Are people free to leave Facebook?
Me, I need an account with Google for my job. Will they now only be allowed to demand I consent to the parts of the data processing necessary to provide the services I use? Or in other words, since I don't rely on their advertising, does GDPR mandate that opt-in to tracking for ads must be optional?