The drawing of the circuit might be copyrightable, but the actual circuit, no. The same principle of “utility work” apples to the circuit.
But you are right about depth of pockets. For the small user, there is no useful protection afforded by copyright laws (I know this from personal experience!). For the big company, they can harass you and drag you through the courts with nuisance law suits, which you must defend, and force you into a settlement even if you were not at fault. Apple have proven excellent at this sort of unethical legal shenanigans, I would certainly not follow their example.
Not really true, the reason was not the PCB, but the OS: “Apple Computer, Inc. v. Franklin Computer Corp., 714 F.2d 1240 (3d Cir. 1983), was the first time an appellate level court in the United States held that a computer’s operating system could be protected by copyright.” (wikipedia)