I, also, generally agree with the above, particularly with the further refinement, that the above is really for PV circuits, as stated by KentO, especially for MPPT CCs.
For PV cables, feeding PWM CCs, cable voltage drop can be a bit more of an issue, but the target system does NOT use a PWM CC ...
And, of course, voltage drops in battery interconnects and inverter cables, voltage drop can be a very important consideration. Generally, the lower the system voltage, the greater the importance, due to higher currents for a given amount of power being handled. 2-ish percent drop on interconnects, inverter cables, or on the CC-to-battery cable would be excessive. For the CC to battery connection, one should also try to add some drop that exists at current in the circuit beaker that protects the CC to battery cable, particularly on systems that have considerable Opportunity Loads, during Absorb.
Not to try to lecture, too much.