If you are wondering why Muslims seem to have been trained to mostly attack the Bible, then one of the obvious reasons seems to be that, the Muslim scholars have realised how empty the Quran is of useful information, while the Bible is full of enlightening things from our God, so they know that the Bible would easily win if a direct comparison was done, which means that it is better for the dawah Muslims to avoid reading from it if they can and this is why I have recently been trying to force them to read from it, so that they can struggle to find a sensible answer, to the questions that I have been asking them about what is written in it.
In this conversation I have decided to jump on what seems to be an obvious mistake, where the Quran calls itself a book, while we know that Muhammad did not have any kind of book given to him in relation to the Quran, so this shows that it must have been something that was added later, before they had finished coming up with a history for Muhammad.