System logging messages disappear after about 90 seconds

I'm having an issue with logging on my system (Sonoma 14.3.1), in that log messages disappear after 60-90 seconds, despite logging being configured to persist. This seems to happen across all subsystems.

The symptoms are:

• Watching the log stream in Console.app, messages older than 60-90 seconds disappear, even if no new messages are coming in. • log show --last 2d only returns messages from the last couple of minutes.

I've filed FB13616761, but wondered if anyone had any other insights or suggestions. TIA