Back when this came up before, I felt and stated that Ford's primary concern was cost. The plastic pan was said to be 30-35% cheaper than metal. The plastic pan sells for over $300!! So assuming that Ford keeps consistant margins on parts, that would put a metal pan in the $400ish range!!

It is now said that the new metal pan is $5 cheaper than the plastic pan.

So I figure that all that other hi tech talk about the attributes of the plastic pan was just marketing.
I wouldn't be a bit surprised to hear Ford touting the new metal pan as being superior. Marketing again.