I have been using silver interconnects for 40 years or so. Siltec. The old blue ones with silver writing. Indeed, the issue now comes to mind as to whether there has been deterioration in that time. Oxidation if air can get in. Probably can. Still, they seem to sound the same as they always did, although my hearing ain't what it was.
The ones that made the biggest difference are the tonearm cables. Presumably because the music signal they carry is so low voltage.
Apart from what I hear as purer sound with less noise, most silver cables seem to be more flexible than copper and so easier to route where I want them to go.