Are you holding your DEC too?
Right now I am doing that card flipping thing. Recently I won my first golden legendary card so after selling it I had a bit more funds for bidding. But perhaps bidding on golden legendaries is not the best idea. I had problems selling Djinn Muirat now I am trying to sell golden GRUM FLAMEBLADE and it is also not happening as fast as I would like. Having a big part of my funds frozen in one card may not be ideal. So most likely I will stop buying golden legendaries once I will sell GRUM FLAMEBLADE.
As price of DEC declines, perhaps what people are willing to pay declines too.