Unit files are a neat concept I don't want to miss again, but everything else done by Lennart seems to be an inceasingly stupid mistake born from hubris.
If all you are using sudo on is a personal (i.e. single user) laptop/desktop to install packages, this (along with other things like pkexec or doas) would seem to present no issues (and personally, from what I can see, I'd be happy to run `run0` on my personal systems!), but sudo does significantly more than that, as is called out by the systemd devs in the linked post https://mastodon.social/@pid_eins/112353324518585654
sudo supports not just LDAP (for multi-user systems), but include various levels of logging (including logging stdin and stdout of commands), apparmor and selinux profiles, the BSD and linux audit subsystem and more in a simple, easy to read and edit config format (this is just me reading from the `sudoers(5)` man page).
Whereas it seems `run0` won't have a `sudoers` file, but will instead be configurable (implicitly) via polkit, which uses JS to write policies (which I'd view as a much harder and error-prone system than the current `sudoers` format). It's not clear to me how much of sudo is tied to SUID vs. having a separate daemon (i.e. how much would have to be ditched vs. how much could be mapped over).
I do feel this is systemd moving away from traditional multi-user unix systems to being a single-user system (targeting the laptop/desktop case, or where sys-admins are the only users of the system, and it's basically a container host).
Of course, once distros start to say 'wait, why are we shipping 3 different privilege escalation systems again? Systemd is needed for starting units anyway, so lets just drop sudo and su'