The inverted loop helps to prevent the liquid refrigerant, that migrates to/condenses in the evaporator coil in the off cycle, from running down the suction line to the compressor on start-up.
That is the reason pretty much every equipment manufacturer, and piping guide, calls for the inverted loop when the coil is above the outdoor unit.

As has been pointed out, depending on how the piping inside the coil enclosure is piped from the factory, and the orientation of the coil, the suction line may already be routed higher than the rest of the coil before it even leaves the cabinet.
I always rout the refrigerant lines up after exiting the cabinet anyway.