I don't see why OA should be removed.
There are many books that are problematic to our current way of thinking: To Kill a Mockingbird, Adventures of Huckleberry Finn, Little House on the Prairie, Uncle Tom's Cabin, Heart of Darkness, Peter Pan, the Allan Quatermain novels, ...
Most of these are in the public domain, but if a customer buys a printed copy, then a publisher makes profit of this purchase.
Then there's also confirmation bias. If I'm actually searching for racist or insensitive content, I will find it. Tolkien, for instance, told his publisher in 1938 that a German translation of The Hobbit could go hang because the German publisher asked if he could confirm that he was of arisch origin (i.e. not jewish). He could confirm this, but he refused to subscribe to the race-doctrine. On the other hand, he wrote in 1958 that Orcs were 'degraded and repulsive versions of the (to Europeans) least lovely Mongol-types'. So perhaps I should add The Lord of the Rings to the previous paragraph.
Removing a book means that you make any future discussion or analysis impossible, or at the very least biased.
Even Mein Kampf is still purchasable for academic purposes. Doesn't disregard the general opinion that it is a vile, antisemitic book.