Fedora is where new and shiny lands, with a release schedule of every 6 months, and ~1 year of support per version, with minimal backporting of bugfixes and frequent package updates. Lots of packages (including the kernel) update freely. That would not fly in CentOS.

CentOS Stream is the next minor version of RHEL. There is lots of backporting patches, ABI stability, the works. And it is supported for as long as RHEL is supported (the standard tier anyways) because it is the next minor version of RHEL.

For a visual metaphor:

Fedora ---------------------------------------------> CentOS Stream --> RHEL

The development process works basically like this:

1) A new RHEL release is created from a rough snapshot of Fedora. It's not an exact copy of Fedora, a fair number of changes are made in the process.

2) Fedora keeps moving forwards quickly, RHEL stays put

3) CentOS Stream takes the most current RHEL release and starts layering updates on top of that

4) After a couple of months these updates from CentOS Stream are then pushed into RHEL as a new point release

5) Repeat steps 3 and 4