You can get much better performance on DX9..DX11 by using DXVK which doesn't have much in terms of game specific hacks. Intel simply didn't put much effort into

You can get much better performance on DX9..DX11 by using DXVK which doesn't have much in terms of game specific hacks. Intel simply didn't put much effort into implementing the older APIs despite there being thousands of games out there relying on them. At this point it might be smarter for them to assist in DXVK's development and making that the official way to play older games instead of redoing all the effort that AMD, Nvidia and of course DXVK devs have already done.