Just use a banana, no one can’t tell the difference anyway

Banana plugs are a thing, and might even have plugged into the hole on the RCA jacks (probably not as they’re usually too wide, but it’s technically possible… I think - never tried it myself). However, they’re single conductors, not dual like RCA plugs are.

ETA: And, yes - I’m aware of the recent Tom’s Hardware article you’re referencing.

In a blind test, audiophiles couldn't tell the difference between audio signals sent through copper wire, a banana, or wet mud — 'The mud should sound perfectly awful, but it doesn't,' notes the experiment creator

Who knew listening to a banana sounded so good?

Tom's Hardware