Confusion regarding JDS Labs Atom power vs THX AAA 789 power

[JohnYang1997]

If you connect headphones via a 3-wire cable, the shared ground wire will increase crosstalk, especially if the headphone impedance is low. With a 4-wire cable, the cable will not influence crosstalk at all. The "advantage" of a balanced connection is that it requires 4 wires, guaranteeing the best possible crosstalk the source can deliver.

Cable is a big part of it. In the end it's the ground impedance. What matters is the impedance between ground join point and feedback sensing point. Cable, cotact resistance, pcb tracing, solder joint etc.
More specifically cable can certainly in the 100m ohm range and contact resistance can be in 30m ohm, pcb tracing can be 10m ohm or more depending on the layout solder joint can be around 10m ohm max in some cases.