Depends on what you mean by "retcon". They showed that refugees did not form 100% of the surviving Bajoran population. But the dialog of "Ensign Ro" is not in contradiction with that, nor is there IMHO any suggestion there that the writers at the time intended Bajor to be empty of Bajorans, any more than Palestine would have been empty of Palestinians or Ireland of the Irish.
We never learned what the true percentage might have been. Bajor was occupied and Bajorans continued to live there, some in roles of forced labor, some simply going on with their usual lives (making whatever concessions were required). But many went offworld, and it does seem Cardassians actively drove them off, rather than trying to cling on to them for labor.
What could be considered a retcon is the change of the name of the folks from "the Bajora" to "the Bajorans". But we could in retrospect just argue that "Bajora" were the emigrants (or even the specific resistance-minded emigrants we saw) and "Bajorans" were the species as whole.
Timo Saloniemi
