Something I always thought odd; why would just _having_ MIDI ports make the ST popular with musicians? Getting an Amiga MIDI adapter was super cheap and easy... although most early Amiga MIDI and stave-notation software (Sonix, Music-X, DMCS) fell out of favour as trackers stormed on the scene; most Amiga musicians preferred to use the Amiga as a sample sequencer than as the controller of other MIDI devices.
Is it really just default ports? If the Amiga had had a line in port rather than required an external sampler, would it have been known as "the sampling machine"?
The Amiga did famously form the backbone of 1990s NTSC broadcast television production as the Video Toaster, but that was because the Amiga chipset was able to genlock with an external video signal, i.e. it was an inherent feature of the machine rather than the default ports and peripherals it came with.