What they were actually pointing out is that increasing the core limit to 16 cores, but arbitrarily increasing the thread limit to just 24 threads, rather than the logical move to 32, is allowing the i9 to operate with all hardware threads utilized, while the Ryzen 9 only has 75% of its threads utilized. It's like the new update to the benchmark was tailor-made to align with the exact specifications of the 12900K, to make it look better against hardware featuring additional threads.
So, the benchmark is treating the 5950X a bit more like it were a 5900X. Which wouldn't matter for most games, but since Ashes is one of the very rare games where performance can scale significantly with the number of cores, it gives an inaccurate impression that the 12900K might perform significantly better than the 5950X at heavily-multithreaded workloads, when in reality, they will likely perform a lot closer to one another, assuming these results are even representative of what performance will be like.
The Ashes benchmark is generally used to compare heavily-multithreaded performance of CPUs, but it's not particularly useful for comparing processors featuring more threads than it supports. So, the 5950X probably shouldn't even be in this comparison, as the benchmark is not designed to fully utilize its hardware. The fact that the developers appear to have updated the benchmark specifically to fit the specifications of the 12900K while ignoring the capabilities of competing processors like the 5950X also brings into question just what other Intel-specific optimizations might have been put in place, perhaps at the request of Intel. Ashes never really was a particularly popular game, and hasn't really had much of a player-base for years, but it still sticks around as a benchmark. And since it's not really representative of performance in almost any other game, it can be thought of more as a synthetic benchmark than anything. But a benchmark that specifically tailors itself to give an advantage to one line of hardware can arguably be considered a bad benchmark.