Many people are familiar with how slurs are sometimes reclaimed by the groups that they're used against, but many other kinds of symbols and narratives can be reappropriated as well. Reappropriation allows marginalized groups to disarm the people who would do us harm.
Most people understand on some surface level that representation is good, but most people who aren't part of a marginalized group don't fully understand why. It's a hard concept to grok if you haven't experienced the complete absense of representation of people like you.