I didn't expect to get what looks like the real answer, without first having to read through the usual sarcasm from the usual suspects, so thanks for that. You're probably right.
Horizons looked like turd on toast though IMO.
Odyssey looks pretty decent.
Horizons seemed like some kind of space wizardry was used to generate the planets though, I know a decent bit about computer graphics and I can barely work out how they did it, it could create some amazing overall looks (just a shame it fell apart once you for a bit closer, or.... Just looked at the "detail")
Odyssey, I know where I would start in creating my own version of such a planet gen system, which is a stark contrast to horizons where.... I would mostly be asking friends and doing a lot of research to try and even begin.
Maybe that helps explain the difference between the systems too.
It would be a hell of a lot easier to make changes and upgrade the Odyssey system, horizons stuff.... You're gonna need some serious, and rare expertise.