Think "The Road", they had no water except what they could very rarely find, and there was almost no food to speak of, so most people turned to cannibalism, and the only food the main characters found was in an underground bomb shelter, and that didn't last very long. In 200 years there would be NO food, NO bullets, and I doubt that any sort of real society would survive 1. the nuclear war, and 2. 200 years of pure anarchy.
The book or the film?, in the book there was an almost permenant winter / pollution haze, due to the "event" happening within six to twelve years max, which led to even basic scrounging being difficult, and no infrastructre.
Plus the shelter in the novel had more food in it, but the dad became spooked.
NV in FO reality they had decades of peace between games and little destruction in lore following those games.
As styles and others pointed out awhile back farmsteads and caravans were plentiful, the NCR took power and unified california after the chosen one paved a way through many factions turf wars.
Settling Power, industry, money, security, and technology, and energy in the hands of groups seeking to work together after, splinter factions within where dealt with.
So litle anarchy there untill more recently.
And NV has water, it has power, it has quite a few developed areas by the sounds of it.
It also has livestock both new and old, wild beasts that may / will be edible. A microcosom of habitats mostly uneffected for hundreds of years.
So its a possible breadbasket, which is one reason for invasion from the factions.