I stated it explicitly before, but perhaps didn't stress it enough:

[The] biggest point I took away home was that Kyon is no rebel. He not just accepts his own fate of servitude, but rationalizes it (”for the sake of the world!”) and gets complicit in it. Perhaps even finds small fun here and there, or tries to ride the dragon. In order to drive the point home, creators trotted out Ryoko, who rebels and dies for it. I thought it was glorious.

Since the above was blogged, I turned the matter over a few times in my mind. I did not want to accept the outcome. But there's really not much Kyon could possibly do, given the circumstances. Events unrolled too quickly to take them in and realize what was going on. In retrospect, the best option would have been getting squished by the giant in the sports field. But normal people only get fed up gradually over the course of years, so there was no way for Kyon to recognize that there was no hope before the critical decisions had to be made. It was a railroad plot all along, a setup made by Anti-spirals.

From this point of view, Ryoko resolved to act much quicker than a human would. Most likely it was an outcome of her greater capacity for reasoning. Plus, she possibly simmered for a while before Kyon appeared on site.

ANDY REMINDS in an e-mail that Kyon is likely manufactured by Haruhi to enjoy it.

By the way, I'm aware of the tilt the source material is taking. Here's a sample from Jonathan's spoiler FAQ (which I've read before watching):

Question: During the First Conversation, Why Does Haruhi Ask Kyon if They Have Met Before?

This is answered in Bamboo Leaf Rhapsody, which will probably be included if there is a second season of the anime.

Andy is known to lean heavily on extra material, he did so when we talked F/SN and Nanoha at least. But I always take an anime-centric view. As far as I'm concerned, Bamboo Leaf Rhapsody might as well not exist.