RH had taken over the Centos project and Board by that time. You’re right that Centos was already circling the drain in terms of resources (I remember waiting many weeks for point releases), but the way they did this was brutal and poorly communicated.
And remember those downstream ‘rebuilds’ only appeared to fill the vacuum caused by Centos disappearing. That they’re both doing very well does make you question whether Centos could have been sustained in its traditional form. (As opposed to Stream, which is only of benefit to Redhat and those in its testing cycle)