RSF forces in Sudan's civil war are preparing for mass genocide

You could just... enforce your immigration laws. Weird concept I know, right? There's this weird thing countries have called Coast Guards, Border Police, etc. Should check them out.

Whenever any country falls into instability, people try to get away as far as possible. A huge chunk of the European populations of North & South America, Australia, etc. were fleeing persecution, war, and just general disorder.

Their only advantage was that these didn't have states organized enough to stop European settlers. Right or wrong, if you don't use state resources to stop refugees, you don't get to complain.