Erm XLR, RCA Phono, and 1/4" (6.25mm) or even 1/8" (3.5mm) are all connectors and only one of them is definitely unbalanced.
XLR is generally balanced (+ve, -ve, gnd) and TRS versions of both 1/4" and 1/8" could easily be wired for those same three electrical connections.
RCA has only +ve/hot and ground signal lines.
1/4" and 1/8" TS connectors would be unbalanced as they only have two poles.
Typically TRS connectors are wires as unbalanced with a common ground shared for both left and right - think typical headphone cables.
Some 1/8" connectors or even those really thin 2.5mm connectors are TRRS 4 pole and might be on some headsets where there is a mic signal as well as left and right and a shared ground.
I guess, for unbalanced connections they are just using the Star Quad as they buy it in such huge quantities it is cost efficient to use what they have.
It's decent cable all the same, low handling noise and decent electrical characteristics for audio signals.