I'm not convinced Russia would get much benefit from from warmer tundra. It takes more than a change in temperature to make land useful. I don't think recently

I'm not convinced Russia would get much benefit from from warmer tundra. It takes more than a change in temperature to make land useful. I don't think recently-defrosted tundra is going to suddenly be profitable farmland. You need the right soil type, weather, irrigation, transport links, workers, energy sources, etc.