There is still the issue of XMP vs tuned memory. Because the X3D is less sensitive to low latency memory doing this for both would favor Intel. Not as much as game selection, or maybe disabling core isolation (optional security feature so can't really argue against leaving it enabled), and likely not enough to have the 13900k beat the X3D in cache sensitive games, but it does seem on par with all of the Intel overclocking done in this review combined and is likely additive in it's results.
Here's a video that just came out on that:
RAM/Memory Tuning & Scaling: Intel 13th gen Core Series [Raptor Lake] - YouTube
And this video clearly uses Hynix ICs, but the tuning seems reasonable for those sticks that use Hynix.