This shit has been going on since the 80s. It’s mostly bullshit instigated by US lumber companies. Available softwood lumber in the US is mainly on privately owned land, and the owners of that land want the price of lumber to be as high as possible so they can make more money. The softwood lumber companies in the US are effectively acting as an oligopoly, and they lobby US politicians for legislation in their interests.

Softwood lumber in Canada is mainly on public land, called “crown land” here in Canada. A lumber oligopoly isn’t possible in Canada because the government would never sell all of that land to a handful of lumber companies. Instead lumber producers in Canada are charged a fee for the logs they cut, that fee is set by the Canadian government, and it is less per log than what US lumber producers want to charge.

Instead of competing on price, US lumber companies lobby congress to impose softwood lumber tariffs for the umpteenth time. When the US lumber companies don’t need to compete with Canadian lumber, they can jack up their prices. When they do that the only people who benefit are the US lumber companies and the politicians they’ve lobbied. Americans pay more for lumber, Canadian lumber companies and their workers suffer.