YouTube doesn't have a defined policy because they say if they do, the racists will abide by it while finding ways to still be racist that don't violate the policy. By not having a defined policy, they can declare anything racist. It's not that they're declaring hacking videos to be racist, it's that they're using the perceived threat of racists using the letter of the law to continue to post racist content as a way of not needing to justify their deletion of anything on any topic without explanation. If racism didn't exist, YouTube would want to invent it to justify their policy of not having a defined content policy.