I'd say it's more like, having a betting shop in Canada, but the only entrance is via an underground tunnel whose entrance is in the US. The US have said "the only use of this tunnel is to disobey US law, and so we're closing down the tunnel."

That analogy leaves me with a few questions: (1) is a "tunnel to Canada" a good analogy for "a .com domain hosted in Canada"? (2) Is it true/ a good thing that .coms come under US jurisdiction? (I think this is the case, but shouldn't be).

The problem arises because, unfortunately, .com domains are based under US jurisdiction. Given that, there's an option for US-local lawmakers to apply for a takedown.