Additionally, the risks to advertisers and websites are quite large, which I'm not sure they fully appreciate (unless I'm misunderstanding something here?) - it's not that the consent form is illegal, after all - perfectly legal to have a confusing consent form. Rather, it's that all the personally identifying information thus collected is illegal acquired and held (and it's hard to argue the violation wasn't intentional, to boot!), and the fines for that can be quite large, and can be applied retroactively to whenever the GDPR came into force. Rules always get stretched, but specifically in this way sounds pretty unwise (unless they're cynically trying to have some subsidiary go bankrupt or otherwise encapsulate the risk).
With any luck, the GDPR norms on this front will become global norms, but it's too early to tell.
A coercive opt-in isn't so much illegal; it's simply void. Having a coercive opt-in would be fine yet weird (as I understand it) if you then proceeded to only retain and process personal information to the extent you would be permitted without the opt-in. (IANAL, and only as far as the GDPR is concerned, perhaps if it's misleading enough that violates some fraud statutes somewhere, but that's a different issue).
It's just a question of how much the companies in question believe that the EU is going to come after them. Once the cost calculus shifts to being on the safe side it'd quickly turn into a norm, but it requires showing some teeth.