I recently updated my TW install and in the User and Group Management in Yast in addition to me there is this under the users tab:
systemd core dump systemd Core Dumper 998 systemd-core dump
systemd-network systemd Network Management 999 systemd-network
My question is are these really needed or can it be safely deleted?
Why would you want to delete them? Like all other users pre-configured in the system (about 20 of them) they are there for a reason even if you do not fully understand that reason.
And specially if you do not understand that reason, it might not be a good idea to remove them.
In this case I assume that systemd uses these users for doing specific tasks that do not require superuser privileges and as you know, when it is not a must to use root, never do it.