Why aren't repeats unfolded automatically in MIDI?

[Raphael Manfredi]

What is the technical reason for repeats to not be automatically "played"
(i.e. unfolded) as many times as necessary in the MIDI output?

The "\unfoldRepeats" is a crude hack, and I fail to see the justification
behind this feature.  Surely, lilypond knows how to iterate over repeats
to be able to process "\unfoldRepeats" so surely it should not have any
problem generating correct MIDI output without this directive.

Why isn't this behaviour "fixed" to behave normally, i.e have MIDI output
reflect the music as written?

Raphael

P.S: Why aren't pralls, trills, arpeggios not automatically realized
during MIDI output?  When playing baroque music, the lack of realization
of those ornaments really changes the way it sounds.  And typesetting
the realization in the score is cumbersome and messes the visual quality
of the score.