Before revision: Egoists may respond that if the situation becomes worse for everybody, that would include the egoist , so it is not, in fact, in his or her rational self-interest to take things to such extremes.
After revision: Egoists may respond that if the situation becomes worse for everybody, the egoist will also be negatively placed, such that it is not, in fact, in the egoist's rational self-interest to take things to such extremes.