I can appreciate that MIDI is data sent to and from a sound card and you need something like a DAW to play sounds through a MIDI keyboard. and in comparison audio is real sounds that are recorded. However; IF I CREATE A PIECE USING MIDI IN MY DAW THEN EXPORT TO MP3, IS THAT NOW AUDIO AND NOT MIDI?

as it can be played on any device that is compatible e.g. cd, mp3 player