Under that proposed contract, there's no way FB/Jack/Goggle could 'negotiate away' access. None.
The contract would provide recourse, and even if it was the blandess of 'mediation', you still have immediate standing to overcome and put Zuck/Jack/DonkeyTwins in the galley.
What Rand is doing -- 4D chess player his own self -- is framing the argument that Zuck/Jack/DonkeyTwins cannot be brought to heel ut ubi est, since NO CONSERVATIVE can currently obtain recourse against these social media fggts as the existing jurisprudence would permit.
These social media giants are unhinged, they are using people as chattel (selling every single view & click you perform online), and thus they must be either broken up or forced to adhere to every equitable user circumstance, whether that is under Section 230 enhancement, or a revised schema that puts social media squarely under 1A settled law.
Summarily, either Zuck/Jack/DonkeyTwins hew to free speech as guaranteed by 1A, or they will be defaulted to utilities status and burdened harshly by the regulatory yoke they genuinely deserve.