[bestorworse]

Yep. It's anyone's guess what's been going on there. Lots of theories out there. IMO Google doesn't consider this a high priority and the cost to keep the development going on considering the engineers working on it is low enough.

Also note that swapping the core of a widely used comercial OS like AOSP would be no easy feat. Imagine trying to convince OEMs, writing drivers practically from scratch for all the devices (based on a different paradigm), the bugs due to incompatibility, etc.