[TomVDB]

PCB routing is generally considered a much harder problem. There are a bunch of reasons that add up, but one of them is almost certainly that a PCB is supposed to look good too. The routing on an IC is total chaos (which actually reduces crosstalk issues), but nobody will ever notice.

[raverbashing]

That's an interesting point

PCBs "look good" because of different production contraints (and I guess because you're mostly connecting tight-timed busses together)

In ICs you're doing the above but also pulling signals from 10 different places together.