They finally realized this whole materia melding thing is fucking up the economy....
If you noticed in 1.0, no one was really selling Materia IV, because everyone was keeping it for themselves.
But when people were selling them, prices were ridiculous for something that had high chances to blow with multiple melding attempts.
Now what they are doing is the right path, Ex melding and more materia for sale = cheaper Materia IV = less money to blow on double, triple, quadruple IV.