RHEL requires expensive licenses. CentOS was RHEL without the RedHat branding and without the expensive licensing.
By design, there was a nearly complete overlap between RHEL and CentOS. By "repurposing" CentOS into a "rolling release", RedHat (IBM) has broken the overlap so CentOS (free licensing) no longer competes directly against RHEL (expensive licensing).
This is so misinformed it's funny. CentOS and RHEL will now be down to the compiler flags compatible since RHEL minor releases will now just be point-in-time forks of CentOS with security fixes and backports from, you guessed it, CentOS.
CentOS and RHEL will only be exactly the same at the moment when RHEL is a point-in-time fork of CentOS. As soon ad RHEL forks from CentOS, CentOS will roll forward and will no longer be exactly the same as RHEL.
Previously, CentOS was a rebuild of RHEL. In between RHEL releases, CentOS was exactly the same as RHEL. When RHEL had a release/fix/backpoint, CentOS trailed until it was rebuilt from the new RHEL source.
The "old" CentOS was exactly the same nearly always (nearly perfect overlap) and the "new" CentOS is exactly the same nearly never (almost no overlap).
You act like RHEL 7.1 is a fixed artifact — it’s constantly receiving updates, security patches, and backports. And CentOS always trails behind on those updates so it’s never exactly the same as RHEL either.
This change makes CentOS so much closer to RHEL that it’s weird that people are acting like the opposite is happening.
That's the whole point -- it's continually receiving updates that never break binary compatibility with existing apps/packages. For example, it's a safe target for vendors to target with binary packages, whereas CentOS stream won't be.
That's true of all RHEL major versions. You can safely target RHEL 6 or RHEL 7 without having to worry what minor version they might be running. The same will be true of CentOS Stream which is the upstream for the next minor release of RHEL. CentOS Stream isn't going to suddenly jump major versions.
If the current RHEL release is 7.x then you can think of CentOS Stream as 7.(x+1). You don't have to worry about it suddenly being 8.0. Fedora plays the role of the future RHEL 8.0.
RHEL requires expensive licenses. CentOS was RHEL without the RedHat branding and without the expensive licensing.
By design, there was a nearly complete overlap between RHEL and CentOS. By "repurposing" CentOS into a "rolling release", RedHat (IBM) has broken the overlap so CentOS (free licensing) no longer competes directly against RHEL (expensive licensing).