Well, I can do a mock -r almalinux-8-x86_64 bootstrap build on RHEL7. (I can't remember whether there are currently any problems maintaining for RHEL8 on RHEL7, but it has been impossible to maintain packages for RHEL N+1 on RHEL N in the past. I just moved to a RHEL8 VM rather than prat about with 7 more.)