I see no purpose to this new ploy making it necessary for players to buy gold and decrease the availability of trading for it. Of course the innocent explanation is that it will reduce the amount of players using gold in the game, but how does that occur as those players usually buy gold anyway. What will happen now, is more and more passive players will leave the game.
The game is too long in time frame to be interesting much past the second or third month and at least gold trading made it useful to stay longer. Now, I perceive players becoming disinterested earlier.