[ardit33]

It is called a 'conflict of interest'. (in this case it is national interest).

Fifa has often rules for this, where it avoid drawing to teams to play together when they are in constant/active conflict.

So, if there are some national tempers flaring, or a war somewhere, it is a better idea to have some boundaries.

Why we hope most people are good natured, we don't live in a perfect world, and it would be insane, or completely naive to believe that 'biases' do not exist.

The other side of it is 'ethnic nepotism', where people hire and favor people from their own countries, creating this pools of mono-ethnic teams in a company which statistically are not probable. This is actually a very common sight in Tech companies and we all know it.