I also think this is a great topic and encourage everyone to start threads on investigating other systems of interest. Well done 
I assume this is so you can capture telemetry data at the same time as certain events happen, but if you’re only interested in having parts of the system react to events without capturing the telemetry, you use pubsub.
Another use case could be that when you’re handling the telemetry event you then want to broadcast some other data, or additional data, than what was received from the telemetry event. So you can broadcast a different payload as needed.
