China has certainly been a winner. As has India directly and Taiwan, Japan, SK, Vietnam, the Philippines, Australia, and Europe indirectly.
To add to your list, China (and India) has been able to take advantage of discounted oil and gas (in the billions of dollars) and profit from various supply lines for both Russia and Ukraine.
Without having access to the counterfactual of Russia rolling Ukraine in a week, it is hard to truly know if China is the true biggest winner in a all-possible-worlds sense. If that counterfactual had happened, would US troops have been in harms way with Putin's next chess move? We will never know. If so, then the US/Europe/NATO are the biggest winners. If not, China is easily the biggest winner.
To your point, in our actualized world, China is the biggest winner. They got all of the benefits without any of the cost.
Given the way this war has played out, Russia's economy, Russia's demographics, etc. Russia will soon be at an inflection point within the next decade. After Putin, either they will atone for their sins and turn back towards Europe (and Europe can't foolishly reject if they do) or slowly fall into being a vassal state of Beijing. If the latter, China will have achieved the biggest geopolitical win of the 21st century offsetting their biggest geopolitical vulnerabilities.