An interesting philosophical insight is that we do not live inside reality, we live in the model of reality we create with our senses, our mind and... our culture, which video games are part of.

The bleu qualia of the sky is a construction of your mind. The Earth as a planet is something you know but you did not experience directly. Same for the pain of others or neurodiversity. Countries you have never been to occupy a similar place as fictional places in your mind. Normal people sort these things well into "existing" and "fiction" but similar mechanisms exist.

Fill this place of examples of criminality and self-centered egoism, and it brings a vision of the world. Fill it with benevolence and empathy and you get a different one.

It leads to very concrete consequences, like the strategy people would choose in a blind prisoner's dilemma game.

but how do we encourage people to actually… move through that gateway instead of just staying at the entrance?

You empower them with tools. When I gave someone a cheap servo, a reaction I got was "Hey, it sounds like the robot in that movie". And there, you realize that the components in that box can be robots.

Games like minecraft or Stardew Valley give a notion of how you can change a place. Or destroy a biome.