> USB connectors do not have the optical isolation of MIDI current loops; USB interconnecting will bring in noisy ground loops that will have musicians and recording engineers pulling out their hair.

Isn't MIDI... digital? What do ground loops matter as long as the signal decodes?

Or do you mean that they'll put current into the analogue signal chain?

IMHO, the correct response to that is to do all hybrid analogue+digital signal processing in the digital domain with opto-isolated pre-amp ADCs, no?