[temp.deduct.call] p3 says

A forwarding reference is an rvalue reference to a cv-unqualified template parameter that does not represent a template parameter of a class template (during class template argument deduction ([over.match.class.deduct])).

The wording in the parenthesis sounds like it is a specific interpretation of what we mean by "represent a template parameter of a class template". However, "represent a template parameter of a class template" should also have its literal meaning.

template<class T>
struct A{
   void foo(T&&){}
};

The case is not about class template argument deduction.

Improvement

A forwarding reference is an rvalue reference to a cv-unqualified template parameter that does not represent a template parameter of a class template (including during class template argument deduction ([over.match.class.deduct])).