The Bible tells us that we are to excel in what is good and be simple concerning evil. (Romans 16:19) That is not a concept widely encouraged, even in Christian circles. "We need to understand these philosophies and ideas and terms and watch these movies and listen to these songs and read these books or we won't be able to witness to people." Where does the Bible tell us to immerse ourselves in the world so that we can lead people to Christ? I've never come across that verse. On the contrary, we are to be "in the world, but not of the world." If we ingest these worldly ideas, we will soon find that we are fighting weeds that started with seeds of doubt planted by these doctrines. Instead we must delve into truth. We must consume our mind with good things (Philippians 4:8) and then we will know how to answer. You don't combat lies with more lies, you combat lies with truth. If you continue to fill yourself up with vain philosophies and worldly doctrines you will be giving up time to devote yourself to truth.
So, to all those who have been called "innocent," "sheltered," and "naive." Good for you! Continue to fill your mind with pure, good and noble thoughts. In the end God won't be saying, "I wish you had watched this movie filled with filth so that you could have been a better witness." He'll say, "Well done, good an faithful servant. You trusted me to give you the answers to these questions and controversies."