My experience in Germany is the exact opposite, foreign students are usually the most communicative and the most dedicated at the same time.

And it is not like getting a degree is an automatism. If you are bad, you will fail and drop out. There has been an inflation in grades in the recent years, but most degrees are still hard to obtain and require that you really learn what you are doing.

Maybe it is different in different fields, but at least this is my impression in physics and the natural sciences.