Openness and success are not compatible. Openness does not scale, no matter how hard you try.
Related: Why What You’re Reading About Blink Is Probably Wrong, a Chrome Developer talking about the aforementioned Blink:
When landing a patch in both WebKit and Chromium stretches into a multi-day dance of flags, stub implementations, and dep-rolls, that’s many steps away [from directness].
In all honesty, we may have paid too high a price for too long because of this desire to stay close to WebKit.
Think about it.