>...The total number of aircraft counted during the disarmament efforts post war were something like 15k across the entire Japanese army and navy combined across all types of planes

They were not planning on using those planes for dog-fighting. They planned to use everything they could for kamikaze attacks.

>...why are the 100-200k that died by the end of 1945 from the bombings enough when similar amounts wouldn't have been spread among military targets the US could more precisely hit?

The atomic bomb was the only reason Hirohito gave in his surrender speech to the Japanese people. There also was this:

>...Later in a private letter to the Crown Prince he did not expect to be made public, the emperor stressed Japan’s deficiency in “science”—a euphemism that encompassed atomic weapons—and an underestimation of the United States and Great Britain. He did not mention Soviet entry into the war.

https://www.nationalww2museum.org/war/articles/japans-surren...

>...History already proves that the "One hundred million die proudly" is propaganda bluster.

I am not sure why you say that "History already proves" - we really don't know what would have happened. For example, if in 1944 someone was saying that Japan would have over a thousand kamikaze attacks by the end of the war, you might have claimed that was propaganda bluster, but it turns out that is what happened. If someone had said that 90% of the Japanese defenders on Okinawa would fight to the death, you might claim that was propaganda bluster. Or that hundreds of civilians would commit suicide, etc, etc. This was total war.

>...A big part of the anti-moral-bomb does hinge on the supposition that Japan would not have held much longer and the feared invasion scenario was a case of prudent planning for a worst case that was unlikely to happen.

By the time of the fight for Okinawa, Japan was far past any hope of winning that war, yet it was the bloodiest campaign of the entire war. No one who knew about that battle would have claimed that Japan was defeated. Truman and others just hoped that the atomic bomb might be enough to convince Japan to give up.