I don't completely understand what you're saying, so will say what I think in my own words and see if we're on the same band.
Indies vs. studios, I think that for indies it makes sense to get as quickly as possible to game development, and that means using an existing game engine. AAA devs who create their own engine (and there are few of them) want as much control and flexibility as possible, which means something that's as low level as possible.
Direct3D has been going more general and less conceptual over time. DX10 dropped all notions of specific vertex transformations from the API (world, view matrices, etc.). Some version of DX11 dropped the D3DX library completely, so any notion of organising shaders and any other handholding got removed. DX12 treats resources as memory, and the notion of textures whose memory is handled by the API is gone. In short, Direct3D becomes more and more complex to use, but provides more control. It's aimed at the engine writers, not hobbyists and indies. The barrier of entry becomes higher.
GPU's are already geared towards compute performance. Any game that doesn't have heavy calculations is using just a fraction of the chip's potential power.
The way I see it, things will likely continue this way: the base API's will be geared at general computing, with some graphics functionality thrown in (depth buffer, texture samplers, ...), but growing ever more low level and general. Over this will be built engines, which is what the vast majority of developers will use.