Showing a hashed string wouldn't tell you much as the value is hashed, so it wouldn't make sense to automatically show it in a data grid. In fact, for security reasons, it would be best not to show them on the page despite them being hashed.
In Mendix, the behavior you described regarding the generation of attributes with a type of "Hashed String" in a data grid is expected. Unlike other attribute types such as string, date, time, or boolean, the "Hashed String" attribute type does not generate automatically when you set an entity on a data grid.
The reason for this is that the "Hashed String" attribute type is a special type in Mendix. It is primarily used for storing sensitive information such as passwords or other data that needs to be securely stored. When you use the "Hashed String" attribute type, Mendix assumes that you will handle the encryption and decryption of the data manually.
By not generating the "Hashed String" attribute automatically in a data grid, Mendix ensures that sensitive data is not accidentally exposed or displayed without proper encryption or handling. It requires you to explicitly define and handle the encryption and decryption logic, giving you control over how sensitive data is managed in your application.
Remember that when working with sensitive data, it is crucial to follow best practices for security and encryption to protect the confidentiality and integrity of the information in your application.