I think it's a bit like saying microcode in CPU underpins high-level programming languages - kind of, but good luck understanding what a program does based on i

I think it's a bit like saying microcode in CPU underpins high-level programming languages - kind of, but good luck understanding what a program does based on its microcode translation. OTOH you can mess with microcode and maybe get better performance, but you won't really know before you try. It's similar with ML - much more like alchemy than science...