There's a duality here. Yes, by the nature of the distribution, GPL, and licensing general, Red Hat cannot stop or prevent a customer from distributing RHEL packages and software to third parties. However, Red Hat reserves the right to terminate any existing subscriptions a customer may have as a result of their package distributing. IIRC, the Enterprise Agreement makes it pretty clear the services and offerings provided by the subscription are for the customer and the customer only. Going outside of that violates the subscription's terms, not the softwares' licenses, therefore allowing Red Hat to end business with said customer.

For those concerned about the final year of CentOS 7: it will not be touched. It will continue to see source exports to git.centos.org as there is no parallel CentOS Stream 7 platform. Also, git.centos.org is not EOL either because it is used by other groups than Red Hat, like CentOS Special Interest Groups.