A generated view e.g. of an ADSO exposes all fields with the internal HANA data type.
For instance, a timestamp is exposed as NVARCHAR. This makes the processing in external applications difficult.

Is there any recommended way how to get back to the BW data types?

The only option I know is to create calculated key figures and there cast into the data type. However, talking about 80+ fields, this is not really a good solution.