even the article admits they’re not even trying to produce as much durum wheat as they have been in the past
Who is supposed to try? Durum is quite picky about climate. Western Canada has the right climate, at least historically, but yields have plummeted (perhaps because the climate is changing). That's how we got into this situation.
Our whole agricultural system is broken.
Or perhaps it is the consumer demand is broken? As the article notes, you can use softer wheats in durum's place. It's doesn't quite give the same texture, but it's still pasta at the end of the day. Softer wheats are far less picky about climate, and have been crashing in price of late. The traditional hard and soft wheats are down in price by ~25% in just the last month!