I have used both the front and rear windshield washers, and the flow in back is a gentle stream flowing down the rear windshield. The front washers shoot up to the same height, about 6" maybe. It's not that they are adjusted low, but the pressure is low. The washer reservoir is about 3/4 full.

Of course, the pump is on the outer side, away from the engine compartment...

Update: Read it and weep... [2016 FSM, WW-59], Nissan switches between front and back washers by reversing polarity. Since both pump outlets are separate.... one or the other washer would be affected by debris / kinking. Very low possibility both are kinked. Looks to be the pump is the issue... Snap.