"the best 2d framework for Stage3D is written in it"
This is purely subjective and therefore meaningless. Genome2D is only partially open source, much like Starling design choices made in that framework are questionable, etc. When it was time for us to go the Stage3D road we looked at Starling and were amazed by it's poor quality, performance and beginner oriented design, Genome2D was disqualified by it use of signals, partial open source, so we have made our own which btw some companies had to do too due to the lack of serious framework out there. You probably think those framework are contributing in saving AIR and Flash, I think they are contributing in putting them down just like Adobe itself does.