What files are required to run an ev3 program?
The titles headed with underscores are unneeded. The title is not necessarily required, and the copyright is obviously useless to the machine.

However, none of the other files can be skipped or removed and still allow the program to work.

These others are written in XML, Extensible Markup Language, and are designed for use by both human and machine. The microcontroller needs all the information in these files.