Q. To use Azure AD Connect Health must every user be enabled for Azure AD Premium?
A. Yes. Azure AD Connect Health provides a set of features including:
- Health for the Azure AD Connect synchronization health which includes alerts via email (by default to global admins of the tenant but this can be customized)
- Graphs of latency and activity
- Summary of export activity
To use Azure AD Connect Health which is a feature of Azure AD Premium the tenant must be marked as Premium which means ALL users must be enabled for Azure AD Premium and will not work if only a subset of users are enabled for Azure AD Premium.