A consequentialist would ask, with an open mind, whether burning the libraries lead to good or bad consequences. A virtue ethicist would express disgust at the profanity of burning books.

Despite being a consequentialist (*), I believe that the act of burning libraries possesses such a massive disutility that it is almost always the wrong thing to do. I can elaborate on my reasoning if you're interested, but my main point is that consequentialism and virtue ethicism can sometimes come to the same conclusion; this does not invalidate either philosophy.

(*) Or as close to being one as I can accomplish given my biases.