It would be good to ask the question a little more precisely, the "post-colonial" can have a very different cultural starting situation in the individual countries of different continents. One cannot discuss in the air here, but must do so for certain regions or a certain country. In the beginning, the most important thing is: who gets the power, how can abuse of power control and reduce?
Identities are not stable points of arrival, but are processual. They are negotiated, recreated, discarded in accordance with contexts of power within the structures of race, class, age and sex.
I highly recommend reading a book called Identity, Ethics, and Nonviolence in Postcolonial Theory: A Rahnerian Theological Assessment by Susan Abraham.