> But then “enterprise features” are added behind the closed doors.
And released as open source.
Of course Red Hat backport a whole lot of drivers and fixes to RHEL kernels - that is what customers pay for - to run and old, binary compatible, patched code on existing/new hardware for a long time. And this is how this "branch" differs from Fedora (why would they be porting all this to Fedora kernels, which are always based off fairly recent mainline, that contain all this, really escapes me). It is unfortunate that they are obfuscating the source of RHEL kernel by not releasing the patches, but it sure is not closed.
However, the tip of the development is Fedora. It is done entirely in the open and is a "trunk" (of sorts) for RHEL.
> So Fedora users are used as free alpha/beta testers but never receive the end result which is developed in secrecy.
You are talking as if these are some sort of proprietary features that only exist in RHEL. Can you please tell us which ones they are?
Of course Fedora users never receive the backports of the old stuff. What would be the rationale for that? Why backport what exists upstream already?