The first OLED monitor for the public was released almost 4-5 years ago, yet prices have remained stagnant for the past years. There has been no price evolution whatsoever. Every year, I consider getting one, but I change my mind when I see that prices have sometimes even increased in the meantime. It seems odd to me. I would expect an increase in production of these panels over such a period.
It probably comes down to supply being squeezed for a niche where people will often settle for a higher refresh lcd instead, for larger panels tv is obviously taking up supply and for smaller screens you have laptops taking up that side of the supply.