I always considered leaks the Bikini Builds, they give you a clue as to what is coming, without revealing the real good stuff.
Well, there is new kernel architecture, The driver we use in ProcessHacker causes a BSOD on these M1 builds due to the functions we use having offset and function signature changes indicative of new/removed API's or re-architecturing, also a new CLR engine to name two. Getting early telemetry back from the real world would justify keeping the foundation of these changes and save Microsoft wasting 12 months development on new things that are based and require these changes, only to find out it doesn't work 20% of the time or causes BSODs much later into development and having to revert specific components or drop new features.