First of all, no, systemd as in PID1 does not get logs back from journald. The systemctl command is using the sd-journal API to do that directly from the journal files.

Secondly, I don't, I expect the recent logs portion of `systemctl status $unit` to be suppressed when journald isn't present.

Note that journal-caused slowness of that very command is a common complaint aimed at journald contributing to people wanting to remove it!

With runit, for example, logs are put in a canonical per-service directory.

E.g. `service_directory/service/logs`

Seems like a trivial way to solve it...

Yes, of course that's possible. But that's no generic syslog daemon either.