It's actually a good example. Putting aside corrosion, there is no difference in sound (that's what the meme is about). Coming to corrosion: oxidation will increase the contact resistance which is not frequency dependent. So, at max, it will make the signal slightly smaller but not "worse".
Actually, mixing gold-plated plugs and tinned receptacle contacts is even worse considering the mismatch in contact resistance
Nope. There is no data to back that up.