There is no real argument made one way or another. If we look at the linked article there are real arguments as to why people don't like C++. Templates, multiple inheritance, and a whole other range of stuff. All Linus is yelling is "I hate C++, I hate STL, them Boost guys aren't worth anything" with absolutely no reasoning what so ever.
As a project leader it is okay for him to disagree about using C++ within his source code base, and within context it is a perfectly valid email, but to use as an example as to why C++ is bad, it is a very bad email to quote.