Genuine concerns and good points.
I would not be concerned with publishing too many events to the eventbus, since, the purpose of the eventbus is to be the backbone of all the events exchanged in the system. Having multiple eventbus instances complicates the usage pattern as the user has to make a decision of which instance to publish/subscribe to.
I guess we should be enriching Pundit to ignore events based on pkg name, frequency, etc. but that probably should not govern what we publish to the eventbus.