I would like to confirm that there is no way to dynamically get the value of management group id during arm template deployment scoped to the MG level.
I mean something similar to the ARM template function subscription() which returns an object with an Id property that can be used in the template.
I know there is no managementGroup() function, but I am wondering if there is any other trick to avoid having to add a parameter to the template.
This isn't possible today but it's on the backlog... If you want to share your use case for it I'll add that as well to help prioritize.