Look at this from different angles, I'll start by saying that the DBA should own the database. She should should be the smartest guy in the room when it comes to SQL, stored procedures, indexes, execution plans, and SQL Server's security model. Next, the DBA should be familiar with (if not responsible for) any application that touches the database: SSIS, ETL, web services, deployment tools, etc. Even in the cloud, these code centric things still need management.

As for pure infrastructure things like: networking, Active Directory, storage, etc.; that's outside the domain of the database. That's the aspect of our jobs that Azure and Amazon marginalize for us. Five years from now, you'll still be coding SQL, even if your organization has moved into Azure, but you won't be micro-managing storage, networking, and replication.