The framing in terms of colors helps the reader to interpret the thought experiment in terms of "groups" or "teams" — as if there's a "blue team" that you can join by helping, and help by joining. Many readers will quickly [ https://en.wikipedia.org/wiki/Stroop_effect ] intuitively choose to join the blue team, and then rationalize their choice as a strategy to help their blue teammates.

But in fact the thought experiment doesn't say there are teams or groups at all! The reader imposes that part on their own, unconsciously at first, because of the description's emphasis on colors.

I predict that running the same Twitter poll with flipped colors — so that red means "I die, unless a majority of my fellows pick red" and blue means "I survive no matter what" — would yield a majority for blue too. What was previously justified as the "virtuous" choice (blue) would now be justified as the "only intelligent" choice (blue).