It's quite obviously why: because nobody on Earth use Intel graphics for heavy games and 3D applications. It's can handle some games and some applications, but this hardware it's just slow and nobody except some miracle here.
Originally Posted by agd5f
When someone buy $300-600 discrete graphics card expectation is that graphics card will support declared features. Again, I don't see any point to blame any AMD employee or open source developer in person, but company itself is cheated me and sold me product that doesn't work. And it's impossible to get refund just because Linux drivers are permanently broken.
So obviously people will blame AMD for that and they have moral rights to do so.