Sorry but no, we haven’t added first-class support for returning all events associated with devices that share a common system ancestor.
However, attached is a workflow that does what you are looking for. Given a system ID, it returns a list of all devices (up to 1,000) that are descendants of the system. It then makes an event query returning all events that are associated with any of those device IDs.
You may want to modify this to also return the parent system itself to capture any events associated with it.