Yes it would. There needs to be some format for the file that the emulator can read. Nintendo could have made up their own brand new format, but why bother when

Yes it would. There needs to be some format for the file that the emulator can read. Nintendo could have made up their own brand new format, but why bother when the iNES format already exists and works perfectly well? Also worth pointing out, the format in question is just a 16-byte header, the rest of the file is data dumped from the cartridge and would be the same regardless of the format involved.