Because the decisions made there were vague and ambiguous. And due to the procedure and format in which they were adopted, the Primate can unilaterally annul them at any moment.
In recent decades, global Orthodoxy has been engaged in intense discussions concerning possible mechanisms for the establishment of new autocephalous Churches. These discussions have shown that, on the one hand, there are no fundamental differences among Local Churches in understanding the essence of the institution of autocephaly.