My only guess is they have a parallel skunkworks working on the same thing, but in a way that they can keep it closed-source - that this was a hedge they think they no longer need, and they are missing the forest for the trees on the benefits of cross-pollination and open source ethos to their business.
Their leadership seems quite a bit more competent than random forum commenters give them credit for. I guess what they need, marketing wise, is a few successful halo GPU launches. They haven't done that in a while. Lisa acknowledged this years ago. It's marketing 101. I guess these things are easier said than done.