I say, and with God's help: Replacing the endowment is permissible if it is more beneficial for the people and achieves their interests. However, in our case, these books are beneficial in themselves. Even if we are not reading them today for certain reasons, we will read them tomorrow. They are considered useful references for some individuals, and we may need to review a matter in them someday, or someone may wish to read them. It is preferable to leave the old books due to their value and importance, and to bring in other books that also benefit the people. And God knows best.