As best as I can tell, this is someone who's speed-run something like nand2tetris and an intro-to-EDA-tools tutorial, and is now trying to move into GPUs and is

As best as I can tell, this is someone who's speed-run something like nand2tetris and an intro-to-EDA-tools tutorial, and is now trying to move into GPUs and is somehow distraught about how hard it is to make that conceptual leap. And this was picked up by a reporter trying to make a quick article who doesn't fully understand what he is reporting on and thinks it's something more impressive than it really is. To be clear: I think that a decently motivated person can go from "0 knowledge" to a toy implementation of a CPU in a digital logic simulator in something like 20 hours of focus or so (especially if the digital logic simulator gives you prebuilt components for things like adders and memory). I've never done digital design for circuits before, but I imagine it's a similar level of difficulty. From parsing the Twitter user's comments, the GPU confusion seems to be the Twitter user skipping any attempt to learn advanced computer architecture because he thinks it's not on the critical path to building a GPU and doesn't realize that the information he's struggling to find is really just computer architecture 301.