I wonder if it might be some totally clean sheet of paper OS design but also capable of running Android applications in an emulation/virtualization layer. I think they know that any mass market handheld smartphone consumer device isn't going to succeed (windows phone) unless people can easily install all available apps from either the google play store or apple app store.

App store inertia has to be the decisive roadblock, and yeah, there would need to be some workaround.

This could also be where China gets another win because of their de-Googled Android-not-Android ecosystem which would enable more competition in their local market than can be achieved elsewhere.

But honestly, why do that when there's already a good, open-source(ish), well-designed, highly secure operating system platform that already runs Android apps? Any new clean sheet OS is either going to be worse than Android on one or more of these dimensions, or it will be absurdly expensive to vibe code.