There's a ton 2013 RGC's for sale, period. I think part of it is that people wanted the newer '15s and there's also a lot of first-time buyers that buy that huge bike, never ride it much, and then sell it off at a huge loss.
I fell in love with the '13 CVO RGC (tan/green) when I first saw it but just couldn't do the sticker price so went with the plain Jane RGC in Candy Orange as my first foray into HD motorcycles (but not first bike - riding for 40 years!).
After two years and deciding we liked the HD enough to keep it but needed to put some stuff on it (stage one, better suspension, etc.) I wandered into the local HD and there was the one I wanted with less miles than mine and a price I couldn't walk away from.
So, for me at least, I'm very happy so many people are bailing on their used CVO's!