That graph is of power consumption, not efficiency. In the 12900K review, the companion graph for performance is at
10:18, and shows the 5950X - at that power draw (
see 24:38) - finishing the render in 9.3 minutes compared to 16.5 minutes for the 10900K and 17.5 minutes for the 11900K. So, for this workload, the 5950X is
dramatically more efficient than the 10900K, and even slightly beats the 12900K (9.4 minutes, so really not by a lot), despite it running with Intel's ludicrous 241W unlimited boost "stock" settings against the stock 5950X's limit of 144W. The 12900K can be reined in dramatically and will run far more efficiently if the power limits are lowered, but it's still slower in Blender than a 5950X. But the 5950X definitely beats the crap out of the 10900K in this testing, even when both are limited by similar long-term power limits.