1. The more emotional characters in the cast will not be willing to face the same truths, and as a result, they'll consider you to be cold at best, and a soulless monster at worst.
2. The audience - and, far worse, the writers - will often agree.
Let's face it: for the vast majority of the audience, coldly pragmatic characters are neither relatable nor reassuring.
People don't want to root for the guy who will kill 100 babies to stop the world from being destroyed, even if the world being destroyed means those 100 babies die anyway. They want a guy who will find a way to save the world AND the babies.
If you want to start a lively debate on a forum, saying the relentlessly pragmatic character isn't evil or a psychopath is right up there with advocating an unpopular ship or deriding a beloved character who died a tragic death.
And no matter how many lives this character saves, or how horrible the catastrophe they avert, it seems that the most effective way to make a highly practical character likeable is... to show their less practical side.
Forget about objectively proving the rightness of their choice, demonstrating that they're saving more people than they kill, or showing that they had no better options. People don't care about that.
Instead, tell the audience that this cold monster is doing it all because they really love one of the people they're trying to save, and they instantly become more relatable and easier to root for.
How powerful is this tendency in our collective psyche?
Consider these two scenarios:
1. The antagonist is trying to stop an alien invasion that will eradicate his species, and he tortures a protagonist who refuses to help him in order to obtain information that could lead to the salvation of his race.
2. To save the scientist, the protagonists blast their way through the antagonist's stronghold, leaving bodies scattered in their wake.
Which side do you reflexively root for? The calm, cool antagonist who hurts your beloved protagonist in order to save billions of lives, or the passionate brigade of Big Damn Heroes who will kill dozens of people in order to save their friend?
From what I've observed, people don't tend to care which side's sins are objectively worse, or which side kills more of the other side's people. They care about the characters whose personalities and worldviews resonate with their own, and they love it when the side they're rooting for is proven right.
Have you noticed this tendency in one of your favorite fandoms?
And which side of the debate do you tend to take?
I look forward to seeing your opinions.