The React developer doesn't need to know how TCP/IP networking works.
The network expert doesn't need to know how a kernel works.
The kernel developer doesn't need to know how a CPU works.
The CPU engineer doesn't need to know how silicon metallurgy works.
And whoever smites metals all day sure as hell does not need to know how to draw pretty icons.
etc.
But all put together we are eating the world.
It‘s beautiful.
Knowing how react works (or doesn't work) helps a designer design a valid experience that can actually be implemented by the developers. Ok maybe they don't need to know React, but surely they need to know what a browser can and can't do.
A react developer (web developer) needs to know how tcp/ip networking works to avoid spending hours of debuging communication problems with XYZ service.
And so on.
Surely people can go about doing their jobs without necesserily knowing how the adjecent stacks work, but they would be way better professionals of they did. I would agree more with your argument if you restricted the distance of irrelevant tech-stack to let's say 3 levels. Eg, the web developer truly won't do any better if they knew more about kernels.
Nobody's trying to build a super rigid structure around the division of labor, they're just trying to create a general set of guidelines that will help answer questions quickly.
>The CPU engineer doesn't need to know how silicon metallurgy works.
You're sure about this?