It's mostly one dude who really went into the depths of it, considered a lot of details and managed to deliver a resolute implementation and presentation. Judging by the Ayn Rand quote, I believe he may ideologically fall onto the regarded side of the anarchist spectrum and may be less motivated by humanitarian aspects, as you may otherwise expect for "crisis resistant" technology. The rest of the small community seems to be made of similar libertarian type individuals, which may be one of the reasons why it doesn't gain more support). Regardless, in terms of economics, I believe the author actually decided not to play, so you may ask yourself, if you may have asked a leading question. I believe the actual answer concerning motivation is this: For the fun, the challenge and the beauty of it. It's a PoC/reference of an idea, rather than the answer to an immediate or anticipated need.

The ecosystem as a whole is a most lovely project to dive into, lot's of nuances to explore. Ideological differences aside, I am positively at awe, what the author accomplished there. Here is a spoiler, something stuck with me: A single RNode is enough to bootstrap the entire Reticulum network stack. It's web-hosting the firmware, software and documentation, everything you need, and every RNode can become a wifi access point for ad-hoc distribution. Beautiful, thoughtful feature you may merely accidentally stumble into, as it's just an understated side-note. The "it's just one guy" critique hits differently, when you see the extent of what that "one guy" actually accomplished.