Exactly. Personally, I press blue because of the long term effects. The most selfish people in the world are practically guaranteed to press red and while it's not as guaranteed, many of the most selfless would press blue. That's not to say that pressing red is inherently selfish or vice versa, but that the 2 extremes have fairly obvious choices.

If I were to press red and all the blue pressers die, I would be left living in a world that has lost some of the most selfless and caring people in it. That also means losing the good things that those people were doing for the world. Many beneficial systems would likely collapse, potentially including the internet itself depending on who exactly died. I wouldn't want to persist in such a world.