Re: There is a reason ...
Pardon my ignorance (I don't use a distro with systemd) why bother with networkd in the first place if you don't have to use it.
Mostly because the old-style init system doesn't cope all that well with systems that move from network to network. It works for systems with a static IP, or that do a DHCP request at boot, but it falls down on anything more dynamic.
In order to avoid restarting the whole network system every time they switch WiFi access points, people have kludged on solutions like NetworkManager. But it's hard to argue it's more stable or secure than networkd. And this is always going to be a point of vulnerability because anything that manipulates network interfaces will have to be running as root.
These days networking is essential to the basic functionality of most computers; I think there's a good argument that it doesn't make much sense to treat it as a second-class citizen.