Take a look at the latest review of a game here on VRAM use which is just one more example of the 'need moar VRAM' hysteria being nonsense. An entry level gamer on 1080p with 8 GB isn't going to be using ultra settings to begin with and a midrange gamer is fine with 12 GB even on higher settings at greater 1440p.
When people argue opinions over facts most people go with facts and that would mostly explain Nvidia's dominance of the consumer market. Yes, a part of it is mindshare but there's nothing that AMD or Intel can do about that except compete by actually competing and not by slapping unnecessary gobs of VRAM on their specs. That is why their commitment to much improved RT performance in the next gen is smart.