Public land in Nevada (and many other western states) has a long history of being ‘stolen’ in various ways. There is quite a racket around it, actually.
For instance, if you drive along I80 east of Reno, once you get away from the city, that land is all BLM. Yet it’s gated off, with incredibly difficult to get gate access. If you call around, you’ll eventually talk to the person who controls those gates, and eventually figure out that those gates are closed for a variety of ever changing reasons.
For a given gate, I’ve heard everything from ‘National security’ to ‘Nevada state law and interstates’ to ‘only utility companies’ to ‘only directly approved persons’.
Once you know the local roads, it’s trivial to get to the other side of those gates though, just a bit more out of the way.
I’ve also seen BLM land gated off by private gates, and individuals threaten people trapped on BLM land due to those gates with fines for ‘trespassing’.
They shut up pretty quick when I pulled out the map showing it was public land, and started quoting the Nevada law they were violating with the presence of their gate though. All the sudden, the lady they were threatening (in this case) was free to go.
When I was in Nevada, I kept a pair of bolt cutters in my truck. And a gun.