This is a very interesting observation that is likely a little less nefarious. I would suspect that the new Windows is first and foremost programmed for Intel's Thread Director in the scheduling department. To word this generically, Windows 11 is less capable now of using a traditional multi core processor and needs the core moderation capability of a thread directing feature for full throughput.
Conversely, what this means is that when AMD implements its own big.LITTLE by integrating its bobcat/beema cores with (Zen 5?), they get a free 15% boost. They'll have to have a Thread Director as well that Windows can talk to.
https://www.tomshardware.com/reviews/amd-tablet-processor,3813.html