I think the point of pub/sub is that all sides only know the topic and no sender or receiver. This could be a bit more explicit. It reads "events are pushed out

I think the point of pub/sub is that all sides only know the topic and no sender or receiver. This could be a bit more explicit. It reads "events are pushed out to customers" and while they may eventually arrive at the customers, you push them into the channel. Great for loose coupling, but you must take care not to code any implicit assumptions about a sender into the customers by accident.