In a DC circuit, are there any reasons for wiring overcurrent protection such as fuse or pptc PHYSICALLY near the load?
You seem to be thinking that the protection is against external power sources, but I'm not sure why.

The far more common fault is unwanted loads, such as insulation failures leading to short-circuits. This is why you put the protection near the power source &mdash; so that it can protect itself from failures in both the load and the wiring.