Semi by hand got out of hand (HA!) in the nineties. There is simply too much work for humans (millions of transistors) so we swallow performance hit. Synthesis puts stuff together from human optimized basic building blocks. Same reason FPGA tools quickly advanced from schematic input to hardware description languages.

With PCB its all still quite manageable, even something like whole PC motherboard is easily doable by two-three EEs specializing in different niches (power, thermals, high speed digital design).