The reason might seem odd. But it ocurred to me that if you want to use immigration to reduce crime, including rape, the obvious solution is to ban all male immigration.
That shocked me because it seems so wildly discriminatory. Yes, most violent crimes are committed by men. But very few men commit violent crimes. Banning male immigration would punish a large group for the appalling actions of a few. Making it about "$some_country's men" doesn't seem a whole lot better. It's still unjust to punish someone for someone else's crime.
If anyone is curious about the exercise, I recommend trying it. It was disconcerting to sit with the idea of banning male immigration, really seriously consider it and realise how viscerally shocked I was by the idea.
Edit: for context, in the UK right now, phrases like "rape gangs" are part of the debate/argument about immigration.
There's nothing racist about the facts. How one responds to it can indeed be racist -- ie. "all people of one of said nationalities are like these ones" would be racist. But observing that a nationality of immigrants are vastly overrepresented is just using your eyes to observe reality.
Disallowing someone from immigrating is not a punishment because there is no right to immigration anyway. In fact I believe we should go even further and see immigrants as investments. If the immigrant is unlikely to have a net positive tax contribution (or at least not being a rapist, for a more realistic target), I don't see any reason to allow him or her to be here. If you accept this idea, there is nothing wrong with training a neural network on characteristics of existing immigrants to predict the future value of a particular potential immigrant.