The final 3D map models can be printed directly from Photoshop or first exported as an STL file, for example. There is no 3D printer available right now? Just use an online service for 3D printing or search for a local 3d print shop.
The possibility to create real 3D maps is a big advantage over the Terrain generator. Especially when it comes to subsequent changes. But also further editing for animations, modelling or 3D app games is possible. Therefor Photoshop offers several file formats for the export.