https://www.corsair.com/us/en/Categ...upply-Units/hxi-series-config/p/CP-9020072-NA
With the inclusion of iCue digital circuitry to monitor/control the psu, things like switching single/multi rail are internal whereas on the HX it's a physical switch in the back of the unit. The iCue allows for setting fan curves, on/off limits for the passive mode temps, rail monitoring etc. Many couldn't be bothered with that kind of information, it's another cae to wire, takes up another USB2 port that may not exist in their pc, etc.
One reason why it's fine by me to have standard cables is that if I was going to use a unit such as the HX/i series in a pc, I'd want to use custom sleeved, color co-ordinated cables anyway, so paying a few $ extra for sleeved cables I'd not use is a waste. Being fully modular, I'm not worried about hiding unused cables, so clutter is minimized. Not everyone is ok with plain black sleeves. Black/red used to be the color of choice, today it's white or white/blue, so black sleeves make little sense.