I dunno, I always thought it was meant to mimic organics.
"Cable management" inside the human body is horrendous. So it felt like in the mixing of machine and biology, the machines had to become more biological in the way they worked to function properly in tandem with the Borg biology.
That's exactly it. Cable management is a top-down design philosophy. The Borg are a collective that organically integrates biological, mechanical, electronic, and any other systems that they find useful--it's quite literally the polar opposite of a top-down design philosophy.
It would be more surprising if the Borg had tidy cable management, because that implies some hierarchy. Actually, the Borg cubes are a little out of place in that regard. Spheres or fractal-ish structures would make more sense.
I don't know, the drones in First contact didn't had an issue working on the hull of the Enterprise. But Enterprise hull might be an edge case, as in "Not really Borg but soon"-technology.
On the other Hand, the Borg assimilate anything they get their cable management on (eg. the doctors mobile holographic emitter).
But I don't really know much of the deeper Borg lore.