However, it's clear that constraints would not be manageable for virtual functions. Indeed, the comment during the example in p6 also reads more specifically that "virtual function cannot be constrained ".
Now, one might think that the part of p2 "ignoring trailing requires-clauses" does not necessarily mean that they can be present, and it might be read, instead, as a kind of confirmation that they cannot.
However, why specifying such a detail only for trailing requires-clauses, not even for type-constraints, and requires-clauses ? I mean, even these other forms of constraints cannot be present, from
§13.7.3 [temp.mem] - p3 and p4,
p3: "A member function template shall not be declared virtual."
p4: "A specialization of a member function template does not override a
virtual function from a base class."
I guess that, for consistency, the part "ignoring trailing requires-clauses" should be removed.