The quest to return to a small degree of genetic variation would be, genetically speaking, deleterious to a population. Everyone would have the same alleles at one locus.
Many detrimental consequences result from genetic uniformity.
Moreover, decreased genetic variation in a species diminishes the potential for natural selection to act, which would compromise its ability to adapt to environmental fluctuations. From what science tells us thus far, the existence of a homogenous species is nearly impossible. Even if that goal could be reached, that species would be at a genetic disadvantage comparatively. Science has revealed that alleles exist in all populations all over the world in some frequency. This trend is defined as a cline.