First of all, as long as Tu didn't say "not so good" or "can't learn anything", since he came to Germany, please believe in the level of German universities;

Secondly, there is no difference between the two schools, only the focus is different.

TU Cottbus started from the School of Architecture, so architecture and civil engineering are strong majors. Of course, building a house also needs electronic machinery, so it also has these departments.

Tuclauthal started as a mining college, so energy materials and mine geology are strong majors, and these peripheral majors like chemistry, physics and machinery are also involved.

It depends on what you want.