I'm not sure about how much story is out, but there will be a hard cutoff you'll find at some point. Biomes are locked off with a weird wall. I've heard 15 hours of content at this point, unless you have fun just vibing in the world.

I just dumped 5 hours into it and its great. It's definitely a little light on some content, but it's got more than I expected (so far).

Gonna drop this here, because I'd love to know the answer too.