Effect on stability
Wing loading also affects gust response, the degree to which the aircraft is affected by turbulence and variations in air density. A small wing has less area on which a gust can act, both of which [I think they are referring to low area and high mass] serve to smooth the ride. For high-speed, low-level flight (such as a fast low-level bombing run in an attack aircraft), a small, thin, highly loaded wing is preferable: aircraft with a low wing loading are often subject to a rough, punishing ride in this flight regime.
IOW, what matters is the ratio of the mass to the wing area and not just the mass (weight) with no context. For example, if you have two round rocks of roughly the same mass and tie a very light wing to one of them (which makes the masses equal). The one with the wing will be more affected by gusts even though the masses are the same.