I believe that in the larger picture it saved even more lives. Russia had just entered the war against Japan and was eager for more than Manchuria.
In addition, the immediate postwar era, and the entire Cold War, was less costly in human lives and suffering because the bomb was used.
Russia knew the end was near and simply entered the war against Japan to shore up its position for reparations after said war was over.
While largely helping the allies in Europe after the Nazis turned on Russia they did little in the Asian theatre.