Right now, machines need to appeal to humans to reproduce, because humans still control important aspects of making new machines. So the machines that survive and have copies of themselves made are those that make humans happier or richer or distract us, in the same way that those dogs that have survived are friendlier or cuter or do useful work for humans.

If humans no longer fed and sheltered dogs, the dominant dog species would probably evolve to be uglier, wilder, more aggressive and generally more wolf like. We should expect the same of the machines.