This effectively means then that if you are in the EU and you'd want to use either Facebook or Instagram you'd have to pay for a subscription then because they presumably won't offer the free-service without personalized ads and since the law prohibits them from doing that then the only way to use either service will be to pay for it..?
To some extent easy ad revenue has given some of these companies a version of Dutch disease, if this revenue falls away for whatever reason they'll need to win out in features or efficiency. Given that I'd be happy if facebook vanished from the face of the earth and that their website is the definition of bloat I'd say they're not doing too well in that regard.