Nihilism means ancient magic books don't create right and wrong and we can use our brains to create our own idea of right & wrong.
My response to myself several years later is that while this is true, what happens when some people's brains create their own ideas of right and wrong, and some of these ideas are harmful, or dangerous etc.
Everyone's favorite philosopher Jordan Peterson says that we can find value and meaning in old ancient stories (like in the Bible) that have been created and changed over thousands of years and used to organize social norms, sometimes successfully (and sometimes detrimentally).
I know a couple of people personally that have such strong egos that they are basically incapable of self-criticism. These kinds of people will make up all sorts of stories in their head in order to legitimate their beliefs or behaviour. These kinds of people can be dangerous, and some might be better off being frightened into following the Bible rather than their own whims.