It seems like you are making the assumption that time and the laws of physics follow the same rules inside the singularity. If we ourselves are inside a singularity, the net result was enough matter to create our known universe… but maybe in the next layer down matter behaves differently and stars can be produced on a smaller scale. Or maybe the matter is heading towards its own scale of big-bang. And what if time contracts to the point that the life of the black hole, and its relative size, corresponds to the life of that universe and its expansion?
A story which comes to mind and presents an interesting theory that could apply here can be found in He Who Shrank.