Why On 160 and 80 meters the received noise floor is set by atmospheric noise (static, lightning crashes) rather than by the receiver, so extra antenna loss attenuates the noise and the signal equally and the signal-to-noise ratio is unchanged. What does improve reception is a pattern that rejects noise and interference arriving from other directions. That is why very inefficient but highly directive antennas like Beverages, small loops and short verticals in arrays work well for low band receiving.
Watch out The choice about mounting 1/2 wavelength high describes what is needed for a transmitting antenna's takeoff angle, and at 160 meters that would be about 80 meters up; receiving Beverages deliberately lie close to the ground. Low loss feedline is likewise unnecessary for the same noise-limited reason.
Low bands: noise-limited, not loss-limited. Trade efficiency for directivity.