They'll eventually perfect the science to the point a man can pass as a real actual woman. But still, the genes can only be passed through the sperm and the egg. Not to mention, the cost to sustain their "lifestyle" isn't quite cheap. These people will be everywhere and maybe even worse people will come into existence that we don't even know yet. But they'll never be anyone of extremely high influence. They'll be everywhere around people who haven't quite made themselves belong to the upper echelon of the society. Remember, trannies make for great administrators of an old empire full of red tapes.