[...]
However, systemd-networkd works as well (and better) with
an easier configuration.
Hm, then why isn't it the default, and what's network manager for?
NetworkManager seems to be a RedHat baby
and has some effort put into a GUI. systemd-networkd has not got a
GUI yet.
It's been deemed that having a GUI is
required for new users (laptop especially), so no default
systemd-networkd