Leadville Colorado is at 10,000 ft. Pretty much grazing is about the best/only way to grow food, but you'll have to supplement with winter hay. 200 acres is probably enough pasture for 5 cattle at most without destroying the natural forage.
If they were really serious about building a utopia, they would be better off buying a few hundred acres in SE IA, W IL or NE MO. Plenty of water, Mollisol and Alfisol soils, enough cold days for a lot fruit tree production, long enough growing season for most vegetables. Yes a few hundred acres are going to cost $500,000k or more, but you could become 100% self sustaining in a few a years.