What bothers those female readers is not the behaviour of the morally flawed protagonist in itself. Rather, it is that the author seems oddly bent on making his protagonist use women for sex time after time, and that says something about the author. Furthermore, the work lacks a female voice that would serve as a corrective to Severian and put his actions in a clearer moral light.
Now, one might disagree with all that criticism, and I remain a fan of the The Book of the New Sun myself. But one cannot deny that within 1970s and 1980s science fiction and fantasy, there is a huge difference between Wolfe and the feminist writers of those decades like Ursula K. LeGuin, Storm Constantine, and Samuel R. Delaney. In our modern age, when critics and ordinary readers have often come to expect the gender concerns introduced by those feminist authors, Wolfe's work can strike some readers as problematic.
Now, one might disagree with all that criticism, and I remain a fan of the The Book of the New Sun myself. But one cannot deny that within 1970s and 1980s science fiction and fantasy, there is a huge difference between Wolfe and the feminist writers of those decades like Ursula K. LeGuin, Storm Constantine, and Samuel R. Delaney. In our modern age, when critics and ordinary readers have often come to expect the gender concerns introduced by those feminist authors, Wolfe's work can strike some readers as problematic.