I believe that the bigger players have already enjoyed economies of scale to such an extent that the RRP that we see on today's models are nowhere near the cost of producing them.
However, due to the limited number of companies who do participate in this market, there is almost a common understanding to keep prices within a certain range (almost like an unspoken cartel?) so that each player has room to benefit.
Will we see sub-1500 FF? Unlikely. Why? Because I do not believe that the companies will be give their FF cameras such a long product lifespan that it reaches that low a price. Perhaps we will see them somewhere between $2,500 to $3,000 and EOL before there's a chance of it going below.