


realtime-setup does slightly more than just creating a realtime group and adding the user - https://packages.fedoraproject.org/pkgs/realtime-setup/realtime-setup/
- adds udev specific rules for threaded irqs and /dev/rtc access
/dev access should be taken care of by the input group, but the irq stuff I'm not so sure can easily be replicated manually/dev/input access, my bad.