You know, hard to say. Web retailers like BikeBling certainly don't help. The three shops within 100 miles from where I live who all sold Niner no longer sell the brand (and this was all post their Chapter 11 filing), including the one I worked at.
When I had originally listed it, for a while, I only ever got sub $2000 offers. FWIW, I was $1970 into it but I didn't intend to sell it just for I paid for it. Most shop bikes I sell are usually about a year old anyway and most of them have a few demo rides on them. At the time I initially listed it the new colorway hadn't been released yet and with a ~ $3400 sticker, I figured asking $2800 and taking $2400-2500 was a score for someone.
In my area the big three dominate (Trek, Specialized, Cannondale). I think I've seen a Niner on the roads/trails maybe once in the 10+ years I've been riding out here. So I suspect a lot of it is recognition. Because a sub $2500 full Ultegra R8000 hydro on just about any decent frame is worth it (IMO).