With a solid conductor, or rather, an alloy or element in a solidus (below melting point) atomic lattice configuration. In such condition, ‘electrical response’ , or electron flow, is restricted to electron orbital ‘co-joined’ pathways in the atomic lattice. This is the situation in what we call ‘DC Flow’ in the given conductor. This relates to named observations like Johnson–Nyquist noise.
In a liquid conductive pathway, things are markedly different, regarding electron transfer conditions and electron flow.
First, to define a liquid conductive pathway, in being one that is occuring at the ‘atom to atom’, or even ‘molecule to molecule’ level. Meaning, no solids in a liquid carrier. At the atomic level – a liquid, likened to that of liquid water.
Under such conditions as a true liquid conductor, electrical transfer characteristics change dramatically, in, for the most part, far more advantageous ways as compared to that of a solid conducting pathway. This, regarding use as an ‘audio’ cable.
The liquid metal cable thus has RF waveguide considerations, magento-hydrodynamic flow and function considerations, as well as retaining some conditions of DC flow characteristics.
A solid metal wire is confined to simple DC flow considerations, and all points above or beyond those DC considerations, with a complex AC audio signal applied to the solid wire cable are inherently a compromise and generate distortion.
This is why there are so many solid wire cable geometries in the world of audio cables. They are all attempts to circumvent a limit which cannot be stepped beyond: the limit of solid wire being most suited in theory and practical reality for simple DC signal transfer, or one singular specific characteristic frequency.