systemd offers a high degree of backward compatibility. If you want to use SysV style init scripts, nothing will stop you. The service(8) utility still works the way it always did on RHEL, as does /dev/initctl. And even if you use these legacy tools and interfaces, you still get new features such as service management with cgroups. If this isn't enough for the people you describe, then I indeed think that they should get another job. Preferably one where they get paid for pointless whining.