How many distros out there are rebranded RHEL. Some of them offer little more than configuration support from a help desk and never contribute changes back. They have relied on RedHat forums for technical support.
At least with ScientificLinux, there is a narrowly defined purpose. It can focus attention on the applications that the select group of users need. They can contribute by improving the quality and usefulness of those applications.
But then what exacly is the CentOS business model?
As for Oracle, I don't remember ever seeing a patch report on the Linux kernel credited to Oracle. If they have done anything then I do not know what it is.
Red Hat has a point in their reasoning. Technical support cost money. However, I see the risk of fragmenting increasing. At the moment, Suse is in a questionable state. The productization of Linux is now primarily driven by Red Hat (RHEL and Fedora), Ubuntu, and Google Android.