el9 x86_64 # ls -lhZd /var/log/stap-server

drwxr-xr-x. 2 root root system_u:object_r:stapserver_log_t:s0 17 May  6 07:50 /var/log/stap-server
el9 x86_64 # ls -lhZd /var/log/stap-server/log
rw-rr-. 1 root root unconfined_u:object_r:stapserver_log_t:s0 0 May  6 07:50 /var/log/stap-server/log
el9 x86_64 # 

needs to be owned by stap-server. I suspect it's caused by the following bit in the specfile, which newly isn't run on rhel:

%if 0%{?fedora} && 0%{?fedora} < 42
echo '%_systemtap_runtime_preinstall' | systemd-sysusers --replace=%{_sysusersdir}/systemtap-runtime.conf -
exit 0