I mean, If there were appreciable amounts of it (i.e. not on the scale of kilograms in or around the earth), so that it could have a measurable impact on planet

I mean, If there were appreciable amounts of it (i.e. not on the scale of kilograms in or around the earth), so that it could have a measurable impact on planet orbits, we could gain information on its distribution within (or interaction with) the solar system. That's why this density estimate is interesting - it sort of determines what the smallest scale is at which we'd have a chance of observing interactions/structure with dark matter.