You mean Square not Sony...
Allegedly Square had something of a falling out with Nintendo...apparently over Nintendo refusing to change to cds ( which could store a lot more info) and sticking with cartridges.
It took a long time for Nintendo to accept the fact that cds were better than cartridges.
FF6 3D Tech demo.
Does that answer your question.You can google the words "nintendo square falling out" and find several commentaries about it.
They seem to have made up, at least to an extent , that's why we're seeing more peripheral FFs being released on the DS.