I see that but upstream means bleeding edge which is not exactly what CentOS users are looking for and if there was something like RH "community edition" which is essentially CentOS (with RH logo) that gets released with a fixed schedule after RHEL (instead of after somewhat random moment for CentOS), it can make people more comfortable instead of relying on the current community to make sure to get their debranding and releasing of CentOS right. And also it may be easier for people to upgrade to RHEL if RH provides an official way from such "community edition".
People like and want the stability of RHEL and relying on the community to get started with RHEL-like distro could be a concern.
If you embrace the existance of CentOS, why not do that fully as part of RH family?
Officially, Fedora & Fedora Server are the upstream for RHEL Workstation and RHEL, respectively.