If you did it often and didn't count your own labor costs, then maybe the average cost would be less, but that's an incredibly specific situation.
> I believe the way Sam Zeloof circumvents the enormous amount of capital needed for a chip fab by relying on modern technology to create 1970’s technology
Yes, exactly.
Old lithographic technology is so crude that you can even use modern high resolution laserjets to print masks (10000 dpi is less than 3 microns).
Even so, 1970s-era CVD, PVD, and plasma etch is still quite complicated, and CMP is impossible (it hadn't even been invented yet). So the devices you can create are significantly integration-constrained.
This isn't hypothetical, I've done it -- in grad school we would send out (I believe) 30000 dpi print jobs on transparent polyester film, and then adhere those to glass blanks to create cheap masks for MEMS fabrication. We had an old Canon i-line lithographic aligner that accepted the glass blanks.
I think the print jobs cost us about $100 each.
Here's the first Google result for a vendor (I don't remember who we used). There's a price list on their page and it looks like they have capability up to 50,800 dpi.
https://hacker-fab.gitbook.io/hacker-fab-space/fab-toolkit/p...
I believe the way Sam Zeloof circumvents the enormous amount of capital needed for a chip fab by relying on modern technology to create 1970’s technology. He simply mounts a cheap digital projector onto a cheap microscope - they didn’t have that advantage in the 70s, and thus it cost millions to start a chip fab. My point is that it could conceivably be doable for an individual to create old computing technology with the advantages of living in the modern world. I certainly don’t have the drive to do it, but I wish someone did.