I think you're right that this will be more painful for Canada, economically, but I'm not so sure about "way more". But politically, it will be much more painful for the US side of the negotiation than for the Canadian side. The Carney administration is on much firmer political ground than the Trump administration. Time is on Carney's side.
>The Carney administration is on much firmer political ground
I don't think so. Time really isn't on Carney's side either.
Carney's new tariffs fall on those who, in aggregate, did not vote for him. The average Carney voter has been very vocal about wanting to pursue this tactic- that's why they elected him. (That average voter is an Eastern retiree whose holdings are generally in real estate, so they don't care about any other economic sector beyond that which keeps their property values high, especially compared to the feel-good Elbows Up stuff.)
But Carney's currently having trouble just keeping the country together at this point. That's why he's approving projects he really doesn't want to approve out West, like those oil pipelines, because the West has credibly signaled that that they might just ban Carney and his Eastern voting block from making law and collecting tax from them if development of their part of the country is hindered any further. But if it's not hindered, they'll grow in political power, which is also an inherent threat to Ottawa's power (just not immediately).
And yet here Carney is- for the second time now- imposing more economic roadblocks that drive up consumer prices and put more people out of work for no reason other than his voting block wanting it that way. "Just retaliate" might be the least bad option for Carney to pander to that voting block, but every concession to them drives the country closer to separation, and that has time pressure too.