There is definite truth in these words, and this statement can be used to make a powerful argument about gender, and the way that Rosalind, when she performs the role of a man, is actually much more liberated to do and say what she wants to do rather than when she is a woman and has to conform to society's expectations of a woman. This is particularly apparent in Ganymede's relationships with Orlando. Rosalind as a woman would never be able to have such a close relationship with Orlando, but under the guise of her clothing, she is able to not only befriend Orlando but then teach him about love and how to treat and think about women. Note what Rosalind as Ganymede says to Orlando in Act III scene 2:
I would cure you, if you would but call me Rosalind and come every day to my cote and woo me.
This kind of opportunity to befriend the man she is in love with and influence his thinking about love and women in general is a massive opportunity, and shows that Ganymede is much more liberated to do what he wants because he is a man. Rosalind as a female is prevented from doing so because of the gender conventions of the time, which are deliberately played with by Shakespeare in the Epilogue of the play. It is therefore more accurate perhaps to say that Ganymede is a different character from Rosalind, but only because as a male Ganymede has more opportunities to do what Rosalind would have him do.