As someone with a degree in mathematics I have to say that there has been nothing more helpful to understanding computer science than my mathematical education. Mathematics allows you to quickly digest new topics and make connections to stuff you already know.

He says he worked in a "CS job", but I am very certain that he worked as a programmer. And learning how to programm is a skill you learn during a CS/math/engineering/physics degree.

Of course most programmers do not need math. But everyone doing computer science does.

The issue here is that he is at a university and expects job training. This isn't actually his fault as it is what companies want, but it really should not be that way.

Universities are academic institutions and a CS student has no more right to complain about calculus as a physics student.