I think one of the troubles here is the difference between a GUI and a command line type app. Very true on a GUI you can hide the extension and display file type in a column, which is what Windows and MacOS both increasingly do. However on the command line its still fundamentally part of the filename, to fix that is a larger job and my suggestion is that it should not be part of he filename, but metadata on the file/filesystem.

The other problem with hiding the extension is that you then have "file name" collisions, two files will appear to have the same name but only differentiate by the "type". I think that's wrong.