It doesn't change human nature and reality. Competition is enhanced through cooperation, they are not diametrically opposed, cooperation is just an extension of competition.
Pretending that cooperation has nothing to do with competition is preposterous. The only reason cooperation came about was because of competition. It is the reason that herds are formed, it is the reason that some of your cells became a heart while others became the central nervous system as each of the cells competed for the proper chemicals to create one or the other.
All life is made in competition and continues in it throughout its life. Pretending that it is somehow 'evil' or 'not natural' is simply outright lying to oneself.