I'm not previously familiar with this dilemma, and having looked it up I am not sure which button lies as the best choice. If I want to hope people will choose blue, it remains likely a majority will select red, not, I believe, out of an innate viciousness, but an immediate fear response, and if you believe red will win regardless of your individual choice, pressing blue saves no one. If everyone were to act in the self-interested and rational fashion, all would select blue, a world with half the population, workers, supply chains, etc., dead, would not be a comfortable place to live. But you act out of fear and distrust and select red for fear that your neighbour will act out of fear and distrust.