Gold plated contacts are a requirement for low voltage signalling
VERY low voltage in a damp environment.
Like medical probes.
Some internal cards and connectors that are only ever disconnected during servicing. Never ever on regularly changed cards and connectors.
Gold on consumer gear, even analogue, is pure bling and inferior to nickel on brass.
1) Has to be ALWAYS gold to gold, because otherwise Electrochemical action, other metal attacked.
2) If a connector is rarely taken out, then tin to tin doesn't corrode. It makes a gas tight joint.
3) Silver and copper are better conductors. Silver oxide conducts so professional connections for RF often use silver over brass.
4) Gold is bad on PCBs for high RF, because it needs an underneath coating that has magnetic properties.
5) Gold near tin causes the destruction of the tin.
6) Even "thick" gold wears too fast. Pure gold is worst being soft.
7) For analogue normal use, nickel on brass is superior to gold and doesn't hurt tin plating.
8) Very high use connectors use brass to brass as it's self cleaning. No good for intermittent use due to corrosion, hence 7.