I’m actually a mod on the Kenshi forums.
It’s not an MMO, and yes there is a demo that includes pretty much the whole game with some limitations (eg on squad size and skill limit).
It’s definitely worth a try for people who like open world RPG. I was especially attracted to the fact that the world doesn’t revolve around the player character as in most RPG :
In Kenshi you are not supposed to be the center of the world (at least as long as you haven’t decided you want to enslave everyone else).
You’ll get your “quests” by listening to rumours for example and “jumping” into the action.
For example you hear that bandits are planning to attack a village, so you can try to protect the village, assault the bandits beforehand or even join them to steal all the delicious pies from the villagers or you can just watch from far away while drinking beer and come back later to scavenge.