Actually, from the assessments that I have read, while new technology and drones have made a meaningful splash, it seems like manpower and the ability to produce large quantities of artillery shells have been the true determiner of the tides. The lesson learned thus far is that considerations from the past still matter.
Russia doesn’t have the capacity to transport that much oil by land. It’d take years to build that infrastructure and it’s not even clear that China is at all interested in supporting huge investments that make them that dependent on Russia. Keep in mind that China and Russia are not fundamentally friends.. Russia is still holding territory that belonged to China, and that China wouldn’t hesitate to take back if they saw an opportunity.
Unless they can transport by sea by the arctic route year round (could eventually be enabled by climate change), the only way is to go south. Which is a far more vulnerable route than oil from the Middle East.