Support a DR (Disaster Recovery) solution with Azure Backup / Geo-Replication
Currently I was only able to get SQL MI accepted by a client because for the DR scenario I was able to manually script client initiated backups that backup to geo-replicated blob storage.
SQL MI does support replication to a secondary site but this makes it too expensive for most clients. But they must have a DR solution as the 7-day point-in-time locally redundant backup doesn't meet their security requrement.
Geo-restore for Azure SQL Database managed instance is available from early 2019.