I honestly like this idea.
Botswana, Namibia and South Africa, already share a lot culturally, politically, and economically: functioning democratic states, regional cooperation, and populations with strong national identity and patriotism.
What I’m imagining is not one country swallowing the others, but a federal union: one federal constitution, one president and parliament, and shared responsibility over the military, foreign policy, immigration, currency, and federal law, while each member state retains autonomy over policing, education, local taxation, infrastructure, and regional laws.
Basically, similar to how federations like the United States or Germany operate: one united country with strong regional governments. A new flag and identity would probably have to emerge from that as well.😭