Intel has flattened out is probably more accurate. Processor speed improvements have indeed not kept pace in desktop / high TDP offerings. A lot has however h

Intel has flattened out is probably more accurate. Processor speed improvements have indeed not kept pace in desktop / high TDP offerings. A lot has however happened in the lower power chips used in laptops/mobiles in the last 10 years. Apple silicon or most ARM type SoC chips of today are so much much better than anything from late 2010s in performance at that power draw. This has also coincided with decreasing desktop demand as more people use phones or laptops as their primary or only device. I don't have enough know-how to state with certainty that it is the just the market movement with more R&D money in lower power processors or if there are hard tech limits but certainly is a factor