who cares what the thing looks like as long as it gets the job done?

Aesthetics (or lack thereof when things are messy) does have some direct unconscious cost to mental load, and a direct tension between cleanliness and horror vacui.

https://ignorethecode.net/blog/2014/11/11/horror_vacui/

And let's not forget, a well-designed system can actually make troubleshooting and maintenance easier. I've seen some beautifully cable-managed rigs that make it a joy to work on. Maybe I've been wrong to dismiss aesthetics all these years... you've got a point, aesthetics maybe matter.

That's where we start talking about "design" instead of "aesthetics"! Dieter Rams's 2 to 6 would definitely apply:

https://www.vitsoe.com/gb/about/good-design