Firstly, this song is satirical. The overall message is that pop music has hollow lyrics that in no way help people who are struggling with mental health or suicide. If someone is suffering from depression or anxiety listening to pop music which tells you to be brave and not listen to bullies will not help you, instead, Bo says to seek professional advice as that is what you need if you are to actually become brave – not a meaningless commercial lyric. He acknowledges that he has struggled with depression and that people need to talk about these issues, he may be implying that comedy can help bring such things out into the open. Burnham uses many common aphorism and sayings, along with metaphors and allusions to make light of a very dark and sad subject.
Link to Lyrics: https://genius.com/4948615