It saves about 4000 km and 4 days off of Vancouver -> Finland, which for one early transit was worth about $200K:

https://www.theglobeandmail.com/report-on-business/breakthro...

There're still a lot of practical problems with the Northwest Passage - notably, the most direct routes are too shallow, there remain lots of icebergs and ice sheets, it's not well-mapped, and there are few resupply ports along the way. I'm not sure I'd agree with all the criticisms in the article (notably, they assume the Northwest Passage will always have ice in winter, but in many "greenhouse earth" scenarios the arctic is ice-free year-round), but it's decades out, not years.

Shanghai to Rotterdam: Panama canal 26000km, Northern passage 16000km....

Not to mention the northern passage isn’t anywhere close to passable by any serious cargo, even in a decade it will be questionable.