I guess that Intel will tailor the 13xxx CPUs to different power needs: from the most demanding, power hungry, 13900k variant that will certainly change all it's power savings for higher clock rates and/or longer durations of PL2 states, to an i5 or i3 variant tuned for power efficiency, at the cost of highest turbo frequencies.
If the rumor mill is to be believed, Raptor Lake will be built on an improved Intel-7 process (some sort of 10+++ nm process), while Zen4 is supposed to be on TSMC's 5 nm process. That's of interest as Zen 4 will supposedly come out late 2022, as is Raptor Lake. These two will compete with each other directly, so Intel's power savings through its voltage regulator may become partially offset by a 5nm process node that will improve power efficiency in Zen4 by at least 20%. Moreover, AMD is certainly not sitting and doing nothing beyond transitioning to 5nm. Instead, they will most certainly have found some architectural changes that would improve power savings even further.
If you run both at suggested TDP, meaning 125w for intel and ppt of 142w for ryzen, the 12900k uses less power than the 5900x but more than the 5950x ,it has lower temps than both the 5900x and the 5950x because the big die helps a lot in transferring the heat to the cooler (less heat per surface) ,and in both efficiency as well as performance it is right in-between the 5900x and the 5950x.
Being able to use twice the power to beat the 5950x in a big part of benches WITHOUT EVEN OVERCLOCKING is just the cherry on top.
If intel can reduce this 125w tdp to 100w it would be massive for intel.