Also in the article it is clearly mentioned that time to market using vega was much shorter than reinventing the wheel which was important i'm guessing since AMD is still small compared to intel in mobile space and they have struggled in the past in this segment.
Yes, though I'm pretty sure the same rationale was used for the 4000 series APUs as well.
I have a feeling that the particular market these chips are aimed at that improving the iGPU by even something like 50% is not that meaningful, it's still not going to be competitive with discrete and will nearly always be pair with one if gaming is an option on the particular laptop.
And so I suppose the rationale might be that it's just easier to stick with Vega and the current power draw for the iGPU as acceptable for the required graphics horsepower. Maybe one day we'll see an APU powerful enough to remove the need for discrete GPU in laptops, not for awhile yet though :).
