RPM/RHEL-Adjacent Distro Summary
CentOS Stream is more stable than Fedora, signs both package and repository meta-data, has a 5-year (hardware) support cycle, and would be easier to transition to thanks to sharing a base with Fedora. See the forum thread for in-depth discussions about stability, age of the kernel, and software availability.
Red Hat’s CoreOS spinoffs (Fedora Silverblue or Fedora CoreOS) offer a very compelling combination of security, TCB size, and rollback functionality. However, their short life-cycle makes them unsuitable for use in dom0 (at least until more functionality is moved out of dom0).