I always wonder the same. I don't need 7nm, even 14nm, but having a way to craft just a bunch of chips, with zero cruft (not too much legacy, simple design ala RISC, a bit of GPU inst, crypt), as foundation for something like redox, or hurd .. would be very nice.
ps: these days, on another scale, I look at flexible PCB and even conductive cellulose (<= for the material is 10m from any windows)
Flexible PCBs look pretty cool, for sure - I saw some sheets made of copper-clad Kapton on Amazon, but they were pricey. Still, I think that's what all those TFT ribbon circuits are made of. I once tried soldering little wires to one of those, and I was amazed at how good the tiny gaps between the contacts were at repelling solder and preventing it from bridging.
the dynamics of solder is quite funny, when you look at all the guys soldering chips with pin gap of 0.1mm; solder paste aggregating on metal contacts and leaving the pcb clear all on itself ..
ps: these days, on another scale, I look at flexible PCB and even conductive cellulose (<= for the material is 10m from any windows)