Requiring companies have an opt-out version of their sites is essentially the same thing as saying trading personal data for services is not a valid business model. It does seem that fundamentally that is the point of GDPR, it would be a lot simpler if they just came out and said that instead of these confusing obfuscations "you CAN use PII if you absolutely need to and the user agrees and you allow them to use your site as usual if they don't agree".
Probably just saying that would be too vague. A law generally can't just point at something and say "don't do that", because it'll leave enough loopholes for antisocial people to drive a fleet of oil tankers through.
