I was thinking the photolithography process might be almost as important as the transistor itself. Without the ability to miniaturize transistors and create integrated circuits, we wouldn’t have anywhere near the level of technology we can build now. A computer made of discrete transistors would be way more efficient, reliable, and cheaper than one made with vacuum tubes, but would still be very limited. There are things you fundamentally couldn’t do with even thousands of discrete transistors that became possible once we were able to scale to millions and now billions.