Re: Backwards world
Whilst I completely agree with you that the onus should be on the firms to justify why they need third party tracking (in truth 99.99999% dont!), but the Problem is Enforcement.
There is basically no government department with the resources to go visiting every company behind every website and demanding to know why they are using third party tracking. Even a scatter gun approach of just approaching those that are most complained about, would be completely ineffective. Big firms would just consider it a cost of doing business to make the fines go away (whilst they continued with the tracking), and only the small guys would get hit.
A law that's not enforced properly may as well not exist...
Biting the hand that feeds IT
