and ?
I don’t understand what you aim to do. You are just demonstrating us that the rpm nethserver-mail-server is not removed when you remove nethserver-roundcubemail.
you can change roundcubemail to another webmail type (eg sogo, rainloop, hordes…), therefore you need to keep all the mail server rpms
EDIt: reading this Email Addresses are still showing after removing SOGo, you explained your purpose.