I don't get how so many people say pressing red is the right choice. Yes, if everyone presses red then nobody dies, but the same is true if everyone presses blue. But if almost everyone presses red, a lot of people die, and if almost everyone presses blue still nothing happens. It would be funny if nobody dies but this was just a test if you are capable of large scale coordination - and everybody who presses red just…
The simplest answer is: are you willing to bet your life on the fact that 50% of people on earth won't press red? For one reason or another, the reason they press red doesn't matter. For you, pressing red is safe, you risk nothing. Pressing blue is Russian roulette.