How do you suggest we get there? Ban unregulated mining farms, only allow them to exist if they have a deal with their local energy producer? It would also require most countries to adopt some sort of treaty.

No one is mining only when demand for energy is low. They're mining 24/7, even probably during peak hours. Even with variable energy pricing, it's still more profitable to keep mining than to let equipment lose value idle. Bitcoin users/miners are externalizing their environmental impact.

Otherwise, perhaps things such as Lighting can help reduce mining requirements, but it's definitely up to cryptocurrencies to find better solutions, not wait for countries to adopt legislation.