Apologies for the delay in actioning this request - the dbus name looks straightforward and it appears this has already been granted. shutdown is a super-privileged interface since it allows a snap to DoS the system - as such, I wonder if this would be more appropriate to be manually connected? As such, +1 from me for manual connection of shutdown, -1 for auto-connection. This leaves +1 vote for auto and +1 votes for manual connection of shutdown. As such, for now I have granted manual connection of this interface. I suggest if possible checking at runtime if this interface is connected (snapctl is-connected shutdown) and if not alerting the user to connect the interface if they wish to use this feature.
However, if you feel this is a widely used feature and still wish for auto-connection then we should follow the Process for performing Snap Publisher Vetting for this to be auto-connected.