What's your expectation for how effective that would be? Let's compare some existing bans, say prohibited cannabis farming:
* Large energy use (lights, fans, pumps?)
* Very characteristic energy use (high, relatively invariant)
* Massive government budgets/surveillance to attack producers
* The need to move non negligible amounts of physical goods
* Moral campaigns by governments and social groups that it's bad for society
And yet the banned-market drug trade revenue is something on the order of 80 billion dollars per year or 220 million a year.
Bitcoin miners, currently:
* Large energy use (fans, HVAC, ASICs)
* Very characteristic energy use (high, relatively invariant)
* Mix of jurisdictions banning or allowing it.
* Only need about 2G / Shortwave radio worth of bandwidth to produce blocks
* Moral campaigns by governments and social groups that it's bad for society
Miner revenues need to be on the order of 10-50 million USD per year to sustain themselves. That's almost 10 times less than the failed (relatively global) "war on drugs"
Add to it that by defecting from national socialist forms of storing one's wealth, rather than just momentarily indulging in vice, one improves their position, I'd suspect your hypothetical ban won't work that well.
How many orders of magnitude more power do crypto miners require vs. cannabis farmers? I don't think you get to say they are equally 'large energy use'.
