I really do not think the climate change debate matters to the point here. The climate changes with or without us, and there is evidence humanity may be accelerating what we are seeing.
But that is not my point.
The important part is that after centuries of exploration, Arctic sea routes are becoming increasingly accessible. That obviously creates opportunities for Russia and potentially gives China a shorter route into Europe.
BUT a route only matters if there are buyers at the other end.

Since Russia invaded Ukraine, Europe has spent years reducing its dependence on Russia. Europe is also increasingly trying to reduce critical dependencies on China. That does not mean cutting China off entirely, but it does mean Europe no longer views either country as the kind of long term strategic partner it once might have.



Seven of the eight Arctic states are also NATO members. Russia is the only one outside the alliance. Even if relations between the United States and Europe deteriorated, Canada and Europe would still have their own reasons to view Russian and Chinese expansion with suspicion.
So yes, an increasingly open Arctic gives Russia and China new opportunities. But having a shipping route and having a market are two very different things.
Russia may eventually discover that by the time the Arctic becomes commercially transformative, much of the market it hoped to reach has already spent decades making sure it does not need Russia anymore.