The net-misc/netifrc ebuild depends on openrc; on a systemd system, systemd conflicts with openrc — the two cannot be installed at the same time. The systemd/openrc conflict is sensible; one can't have two init systems. It's netifrc's dependency on openrc that's odd: netifrc is perfectly capable of working on a systemd system (I've been using it as such for a while), and includes systemd unit files for those systems. But it can't work w/ the dependencies as they are.
I cannot reproduce your claimed block, please provide emerge --info and the emerge output about the block