but why depopulate places which are not overpopulated?


I think this is going to make way for a huge dispersion of over populated countries into lesser populated countries.

I think it's because of European laws regarding migrations,
The numbers are too low to make a huge difference for these mega population countries who are bursting at the seems.

Migrations and breeding is also too slow and I think they are losing patience. It's because their populations aren't too high the reason why when they are decimated that they are going to need a whole pile of people from these countries to replace workers etc......If a 1/3 of Euro country population perished , it would mean they would have to replace 1/3 in a hurry if you know what I mean ...

And so 10M can move into one country in one year as opposed to 10,000 per year normally.

I also think that it's because European countries also have the world resources like clean water etc.

just a thought, but a scary one.