As far as I’m aware, CloudLinux is based on CentOS for older versions, and Alma Linux for newer versions, so it would be in the RHEL sphere of things.
They’re also the company that launched and continues to sponsor Alma Linux, a community run RHEL compatible distribution.
If you’re using universal blue images, that comes built into the image (at least on nvidia images for sure). To get rid of it, you’d have to use rpm-ostree override remove to get rid of it.