> I don't see circuit-as-code taking off with humans anytime soon
I don't agree with this. Circuits aren't really anything more complex than anything else humanity has had to figure out. Most knowledge in this area seems solvable.
Maxwell's equations have been known for a century.
For whatever reason, Software Engineering and Hardware Engineering even though they rely upon the same fundamental physics, are so very different? And apparently can't be reconciled? No. I don't believe it.
PCB layout is as much art and black magic as it is science. I'm not sure why you dismiss the complexity so easily, this definitely is not just a matter of applying Maxwell's equations.
Layout is a puzzle, especially with particularly high density layouts, but some of this is ameliorated by high layer count and fine trace/space boards becoming cheaper. Definitely not black magic. RF layout is black magic, let's not steal their thunder here.
High speed PCBs are RF. At high enough frequencies, traces become waveguides, and the result cannot be predicted analytically. Simulation is your only light in this mess.
> For whatever reason, Software Engineering and Hardware Engineering even though they rely upon the same fundamental physics
Software engineering isn't a thing besides being an ego title.
Software is "ship now, patch later"
Hardware is engineered, it must be correctly designed from the beginning and cannot be easily modified in the field