Saying that social equilibria can shift is not saying that they are very likely to. Rather, it is simply pointing out that a social order that seems natural and immutable can break down. As a consequence, social dystopia is a possibility that we should never neglect. Being aware of this possibility and remaining vigilant about the signs of change is one way to help prevent it from happening.
The best take is that the social
equilibrium is just in our minds and it can change anytime, so is an illusion.