MIDI is a musical scripting format invented in 1982
and continues to be supported (ref: midi.org).
There are myriad MIDI players and software for composition --- such as Cakewalk. But this MIDI corpus
would create demand for specialized software (desktop converters with synthetic option plugins, and musical variations for the primary violin, etc.).
There are 1,126 works in the BWV series
(ref: en.wikipedia.org/wiki/Johann_Sebastian_Bach),
and the works which are performed publicly and
published in recording are about 1%.
It's a job for the library of congress which would be bigger than Pandora!