Duelund DCA16GA

In this wire it is your friend ✌️

I thought the dielectric was responsible for the sound of this wire?  The tin coating is to prevent oxidation.

No, it does not melt off and cannot be removed

I'm not proposing to remove all of the tin coating, just the very end were it gets soldered.  It should be very easy to get off with Scotch-Brite, right?  It should just be a very thin layer.  Copper is a much better conductor than tin.  If you remove the tin, the signal will travel from the copper in the wire to solder to the RCA connector instead of from the copper of the conductor, through the tin, through solder, and finally to the RCA connector.  It's one less layer of a (poor) conductor that the signal has to pass through.
Have you compared cables with and without the tin removed?

The tin plating is part of the sound and Duelund did not use it to ward off corrosion which is no longer an issue with today’s better wire coating.....including oil impregnated cotton. So it is there for the tone. It is a fine stranded copper wire and I would not try to remove the tin, I don’t you can anyway. It is part of the wire.

So yes the wire and cables sound better with the tin. You can buy stranded Duelund copper wire in cotton without the tin. It does not sound as beautiful.