Currently, Incident and Sched. Maintenance subscriptions for a channel is an all or nothing setting which in our experience has led to having a bunch of channels light up with unread messages when an incident is opened regardless of if the incident is relevant to the channel.
Right now, the work around that I have implemented for some of our channels that are component specific is to just turn off incidents for the channel and only leave the component updates for the relevant components enabled. Unfortunately, this doesn't provide the additional context and information that comes with the incident/maintenance notifications.