journalctl captures all syslog priority levels; filtering happens at query time via -p <level>. The existing monitor log command always shows all priorities.
A monitor log filter <priority> sub-command lets operators tail the journal at a specific minimum severity without having to remember journalctl flags.
journalctl -p <level> shows messages at that level and above (i.e., lower numeric severity values are always included — warning also shows err, crit, alert, emerg).
vyos@vyos~$ monitor log priority Possible completions: alert Monitor last lines of messages file and filter by minimum priority level (includes all higher severities) crit debug emerg err info notice warning
vyos@vyos:~$ show log priority Possible completions: alert Show contents of logging buffer and filter messages by minimum priority level (includes all higher severities) crit debug emerg err info notice warning