The answer to this question depends in large part on how you define “critical security studies.” If you see this as any sort of approach to security studies that is critical of both realism and idealism, it would seem possible that critical security studies could become the dominant paradigm. However, if you see this as a theory that questions the validity of the current world order and is based on Marxist thought, I do not think that it is possible.
I think that it would be possible for a theory other than realism or liberalism to come to dominate security studies. This is because both of these theories would appear to have significant problems in explaining some of what is going on in the world today. I would think that it is at least possible that constructivism would come to be the dominant theory in security studies and international relations because of the changes that have occurred in the world since the end of the Cold War period.
However, if we are talking mainly about ideas that come out of critical theory, I think that it is much less likely that these will ever come to dominate. The reason for this is that ideas that question the bases of a system on which the whole world is founded rarely become dominant. For example, Andrew Linklater has argued that the entire system of sovereign states is undesirable because sovereign states are exclusionary. He wants a more just system that would treat all people equally. It is unlikely that such a theory could ever become dominant because it is too different from what we have now and because it seems airy, normative, and unscientific. I would also say that critical theory and critical security studies suffer from the taint of being connected to Marxism. Since Marxism is a discredited philosophy today, it seems unlikely that a theory based on it would ever become dominant, even in academia.
For these reasons, I do not think that critical security studies, in the sense of theories connected to critical theory, will ever become dominant.