China could easily just declare that they'd be willing to support Niger against the ecowas terrorists and then those dogs wouldn't dare to invade the country. I understand how China delivering arms to Russian forces in Ukraine might be too risky (although even then I seriously doubt the West would be stubborn enough to crash the entire world economy and cripple themselves just for their fascist puppet state) but what does China have to loose in Africa?
It seems to me they don't want to get embroiled in a proxy war with NATO. They have a longstanding policy of non-intervention which has kept them free of conflict and able to focus on improving the economic life of their citizens. Avoiding conflict allows the CPC more time to develop its economy and global connections in ways that will defeat the American hegemony in the long run. Every year the forces of capital hollow out western economies, particularly in actual industrial production, while China continues planned development.
We cannot place all our hope for the defeat of capitalism and imperialism in the CPC. It is weird to expect China to stand in open opposition to the global order before it makes strategic sense and will benefit their people.
It's probably relevant to point out that the proxy war that the US staged in Afghanistan was pretty devastating to the SU. The CPC is acutely aware of this and has developed a strategy to avoid this very same situation.