What's stopping your adversaries from seizing hardware? Nothing? So the system relies folks playing nice in the physical world?
The whole thing is a ridiculous fantasy with an asinine threat model.
Either monopoly on violence in the state under whose protection miners operate, or private security for smaller threats.
Miners in China, Russia and Iran are essentially absolutely immune to threats from the West. and vice versa.
It's not designed to gamble and make a quick buck, but to survive even a nuclear war. Just like TCP/IP wasn't designed for streaming porn.
If you’re servers are worth X Billion Dollars that’s attractive to the same sorts of criminals that rob banks. Hell governments have a long history of running drugs and state sanctioned piracy etc. An attractive enough target needs serious security.