The main difference between Data Manager and data scientist is the relationship with the information. While the Data Scientist works with the data itself, the Data Manager is responsible for providing the infrastructure that must exist around the information, at the technical and administrative level.
That is, a data scientist is concerned with both using the data and making it available on a granular level, while the data manager is concerned with issues related to management and other technical or architectural aspects.
A recent report from the National Science Foundation explains this with an example. The data scientist analyzes data representation, code and writes the higher-level policies for data management.
While the Data Manager ensures that those policies are applied, both at the team and business level and ensures that the technical infrastructure that stores the data complies with best practices and preservation standards.
In the world of data, the responsibilities of Data Scientist and Data Manager is the key that makes the difference in the perspective that guides a profession with a great future.