>Establish a business that is in that industry, buy a warehouse for that purpose, get your electrical installed, and then run all your miners through your own VPN or Tor (I've never tried to run them on Tor, because I was always worried about speed/connection problems.) They would see large electrical usage, yes, but that is normal for your registered business.

The comparison with illegal mj grow operation breaks down because long-term profit margins on mining collapse to very small percentages, so risking prison for that would be idiotic, especially as legal operators (that eg. enforce some government blacklists) would have lower running costs due to not having to pretend they are something else. In addition, contrary to a mj grow op, you have to order asics from Taiwan/China at least once every few years which would be very hard to hide (gpu mining is going away).

This even assumes that you can order profitable asics at all, indefinitely in the future. The market is structured in such a way that really big mining companies are incentivized to make their own asics - the design of a sha256 asic is relatively trivial (compared to pretty much all other chips) and ordering directly from TSMC or Samsung would save them a fortune. For all we know, it's already happening - it's not like any mining op has an incentive to tell.

The deciding factor is that in PoW a majority can force anything on a minority - smart regulation would enforce blacklists via orphaning once compliant miners achieve a comfortable hashrate majority, totally killing the non-compliant operations. Legal miners would have an enormous financial incentive to comply: orphaning a minority of hashrate directly increases their revenue.
In the most extreme case, states could start mining themselves to take control of the industry - something that's borderline impossible in PoS, because they would have to buy the staking tokens from the market, and there's simply not enough supply available at any reasonable prices.

Then there's the defense issue: assume a PoW chain has been captured in such a way. If the PoW algorithm relies on asics, users could fork to a gpu PoW, but there's no second move - nothing can be done to fork away hostile gpu miners, short of going away from PoW entirely. Potentially, this could be used to kill _all_ PoW blockchains - a state first makes enough asics to obtain a majority, then kills the chain by exclusively mining empty blocks and orphaning everything else, then repeats the process with gpus. The victory would be absolute and the cost would be in the low XX billions of dollars.
Right now there's really no reason for any state to attack as non-speculative use is very limited - but imagine that Iran somehow switches to bitcoin for all external trade and relies on its bitcoin stash to function. Suddenly an attack becomes a very realistic possibility.

Even if somehow some state controlled enough stake in a PoS system to censor everything, the defense fork can be repeated indefinitely - by deleting deposits of a hostile majority staker(s) on a community fork. For this reason, I expect decentralized PoS networks (those that can be run on home machines and without on-chain governance, not cloud-run DPoS or PoS networks with governance) to never be attacked in such a way - there's no way to truly win, short of total global surveillance I guess.