Even this subjective interpretation shows why the question is so good. Someone on the other side would say the fundamentals are completely different.
It is meant to point out how many people say they would be willing to sacrifice even their very lives for a stranger, but in reality they only sacrifice if they already know others had to sacrifice and now they're forced to.
Like if you took the combined wealth of every person who thinks we should tax people more to help the less fortunate - do they give anything freely? They want others to sacrifice first. I'll believe people would actually press blue in a majority, when I see people who claim we should pay more taxes, voluntarily paying more themselves.
I'd love to live in a world where I was confident a vast majority of people would press blue. But I've literally seen people say they would press blue - then go on to say that in a communist revolution certainly we will have to end the lives of all the bourgeois.
I would most definitely press red, because I don't believe anywhere near half the population are actually that good, and don't think I'm a good enough person to actually think I'd risk pressing blue. (Trump won the popular vote in America, and so based on the rhetoric I hear from my left leaning acquaintances, neither would they)
Sad world really. Also why this question is so good.