It's not to dissuade bitcoin mining. It's to move us away from emitting carbon as fast as possible. Crypto is just sideshow.

Carbon emission are not priced according to their future impact. We need to price it correctly. And it's better to overcorrect rhan undercorrect. The only downside is that this pricing will propagate into the economy (as it should). When it reaches people that can no longer afford to live we can prevent them from dying by giving them money we got from tax.