> I wish the distros just made it simpler to pick and choose which systemd components we use at installation time

I think they do a fine job. The only mandatory parts in most distros are pid1, udev, journald, logins and machined.

I have two Raspberry Pis running Debian, one of them uses connman, the other uses systemd-networkd. My desktops use NetworkManager + firewalld, and so on.