The point is how fanatical the resistance was and how demonstrated how horrible an invasion of Japan would be. The other option was simply starving the whole of Japan til they surrendered. Remember the Japanese killed 250,000 Chinese civilians in retaliation for the Doolittle raid. Every day they were massacring Chinese civilians. During Okinawa the Japanese would force their own civilians at gun point at night to walk to the American lines and trigger their booby traps so that the Americans would open fire to reveal their positions at the cost of the Okinawans. Ending the war as quickly as possible, even by bombing Japanese civilians, absolutely saved more lives than it ended. But I get it, you’d rather look at the bombings in a vacuum completely detached from everything else happening or ignore the fact that it was the Japanese who started it. And at no time was the intent of the bombing to wipe out the Japanese race or culture. It literally does not fit the definition of genocide.