omit command output on systemd-run

when running systemd-run --pty --same-dir --wait --service-type=exec I get all the command output in journal. While nice, it is not something I want/can afford all the time. for example, if I want root to run ls as

systemd-run --user  --nice=+1 --same-dir --collect --service-type=exec --pty --wait --unit MYSYSRUND ls -la

how can I avoid the output of ls being on journal? metadata is fine.