Explain who john means when he thinks that not so many of them of them will come out in the rain

How can we make the world a better place, specifically towards discriminated people (lgbtq+ community, people of color, people with disabilities etc.) how can we make them change their view on people they call "different"? how can we get people to love one another despite how they look or who they love or where they are from? 2-3 paragraphs ! (ᵔᴥᵔ)