Why are European countries relatively tolerant of African immigrants?

In Europe, there are three social policy models to control illegal immigrants: tolerant British policy model, rejected German policy model and legalized southern European policy model.

As for Europe's tolerance for refugees, the reasons are mainly in these aspects:

1. Most of these illegal immigrants are former colonies of EU countries. Europeans feel guilty about these former colonies.

2. The population in Europe is seriously aging and the labor force is insufficient, while the labor force of African refugees is low.

Of course, it has something to do with the relatively tolerant culture in Europe.