Ignoring Vulkan and DX12 just shown how little you understand, its all performance and there is a reason for the huge performance of the RX480 with those API's,
The compute and render throughput of the 480 is actually near that on the GTX 1070 (5.8 vs 6.5TFlops), thats why its much closer to the 1070 with those API's, it is simply bottlenecked in DX11.
Its the same reason why often the Fury-X is little or no faster than the RX 480 or 390X at 1080P, a massively more powerful GPU constrained to the same levels of performance as those much weaker GPU's.
If AMD improve their own DX11 overheads to the levels of Nvidia and add about 100Mhz to the RX 480 they already have a GTX 1070 level card.
With twice the number of shaders Vega would blow the GTX 1080 out of the water, possibly also beat Pacal TX.
Your ignorance of this is causing you to approach it from completely the wrong angle, AMD could make a GPU 5x as powerful as the 1080 and yet if they don't sort their own DX11 bottlenecks it will be little to no faster than the RX 480/.
All IF and BUT's.
Face reality, the only good card AMD currently have is the RX480. It competes with the GTX1060, and that's it.
People care about performance today, the next few months and year or two. DX11 games are here to stay, DX12 has been hugely disappointing so far. This will not change during 2017, or even 2018.
Vulkan is the only good new API, and so far we've had only one frigging game that took advantage of it (Doom).
Vega needs to get a move on, or NVIDIA will have Pascal's refresh and Volta out before Vega even hits the stores.

. Stop being so literal. Stuff happens.
