(Let's rephrase the success part. The campaign was destructive and deadly for the civilian population but did nothing to end the war earlier. Bomber Harris and the Lord Lindemann got a career boost, though.)
Really? To assert this, you need to show not that Axis production didn't decline, but that the damage done didn't prevent production from increasing even more. How does one show that?
Axis production continued increasing, according to this, it tripled after the bombing campaign started.
Actually, it's even worse than that, since one must also subtract from this production the resources Germany was putting into air defense. This effort was massive.
The Germans ended up devoting 1/4 of their war production and a million men to antiaircraft defense.
There is a lot of speculation why emperor and generals surrendered, even atomic bombs may not have been the triggering point as much as soviet declaration of war to Japan at 8 August 1945. Most probably it all compounded.
To assert that the bombing campaign did nothing for the war in the Pacific flies in the face of recorded history. We literally have the imperial Japanese equivalent of meeting minutes where they talk about this stuff and toward the end the sheer destruction of the bombing campaign did affect the credibility of the militarists "yeah we can still pull this off" claims in the eyes of many of the others.
BS