Every era's technology stack was built using the previous era's technology stack. A friend told me last weekend about how the masks for the first microprocessors were cut by hand using razor blades on Rubylith, a film that was designed for screenprinting t-shirts and making art prints. Each mask was then projected down to a smaller mask, which was then projected down for the actual photolithography to make the first microchips.
Within a few years, these microchips were used to power CNC systems that did the mask cutting automatically, which allowed for more complex microprocessors to be designed, which... you get the idea. Now the tech stack for making microprocessors is so advanced that there are only a few places in the world that can do it, factories cost $10-$20 billion each, and the extreme fine scale of the etchings can only be achieved by producing extreme UV light from a tightly controlled plasma.
Literal waterfalls of innovation in the last 200yrs with Photonics in general.
When we harnessed the photon, a step change in all tech. Photography, Photomasking, Photoelectrochemical Etching, LEDs, florophores coupled with ccd/cmos sensors, and of course your beloved structured light.
Also, people had already been using computers for almost 30 years before this technology came along.