And what does this mean of the amateur radio operators who call themselves HAMs?
nit: NetworkManager is not the one provided by systemd in the first place - that's systemd-networkd.
That aside I do wierd networking stuff for a living and here's how I see the available tooling:
* NetworkManager - great for a laptop where you're moving between networks and don't need anything too fancy.
* systemd-networkd - great for servers and other mostly static networking setups, even weird ones.
* If you're doing anything weird dynamically (e.g. experimenting) - disable the above or move the interfaces you are experimenting on to a fresh netns and do everything by hand with the ip command (and maybe udchpc or dhclient if you need a dhcp client, but be aware of how to write your own callback scripts for how to handle various associated events).
I hope we can finish the Debian migration soon.
Some DBus message is not appearing and it stalls out your boot process, finding where it was supposed to come from and why it didn't appear is a nightmare. If you want to use a different daemon than the one SystemD provides for some service it will fight you every step of the way, sometimes even undoing whatever you had to do to make the process work in a random update. As someone who experiments with weird networking stuff from time to time I've been kicked in the nuts by NetworkManager on several occasions.