It doesn't mean anything, just sounds cool to people who don't know the tech well enough. Same reason why your HDMI cable is "gold plated for 10x speed!"
Exact same effect could be achieved by making conductor that very same single-digit % thicker. Which is an order of magnitude cheaper. And ohmic resistance is not that important for audio-cables anyway.
Assuming good contact in connector(s) is achieved, gold-plating does not further help with high-speed signals. What matters here - is wire/cable itself, specifically, tight control over where conductors are relative to each other and insulation, so that impedance is well matched throughout, cross-talk is minimized, etc, etc...