Description of problem: I made an attempt to compile openarena on RHEL8. It would be nice, if EPEL package was built. It compiles from master just fine. Additional info: https://copr.fedorainfracloud.org/coprs/pemensik/openarea/packages/
If you are interested in building it, I'd be happy to add you as a co-maintainer.
Or alternatively you could just drop the opengl-games-utils dep from openarena to make things simpler. I don't really think it's necessary there any more these days as pretty much all computers support opengl.