GDPR still is an opt-out mechanism. Though work for google I don't think it will fundamentally affect them that much...
I am not a lawyer, this is not legal advice.
I guess the crux of the question is in ambiguous terms like "personal freedoms", etc. that the regulation says should be weighted against "Legitimate Interest" of whoever collects data.
One of the main things about GDPR though is getting companies to give a monkeys about the rationale for the data collection - even if they use the legitimate interests argument, part of it is that they now have to actively prepare for that, show the legitimate interest and rationalise it to regulators.