This is true right now, but isn't that largely because the cost of fabricating a VLSI design is astronomical, and the tools to debug any issues with a first run

This is true right now, but isn't that largely because the cost of fabricating a VLSI design is astronomical, and the tools to debug any issues with a first run also cost an arm and a leg? If you could get parts made affordably and have some insight into their operation, then you might see more interest. Sort of like how affordable PCB fabrication services have led to a proliferation of customized circuit boards for all sorts of purposes, including spurious art like conference badges. I bet if it were affordable to get a working design with a bit of studying, you'd see a lot more special-purpose chips, especially in small 3-6 pin packages.