Actually, it depended.
The Strategic Bombing Survey done after the war found a couple of salient points regarding the bombing of Germany and Japan.
1) While the Luftwaffe was visibly contesting the skies, resolve stiffened or stayed the same in Germany.
2) With no visible Luftwaffe contesting of the skies over most major cities (late in the war), absenteeism at work and dissatisfaction with the regime increased. AA guns, even when killing bombers, didn't have the same morale effect. The effect was not nearly enough to overthrow the regime, but it still had an impact.
3) In Japan, when the bombers started hitting the main islands and there was no real counter-attack in the skies, the people started seriously questioning the propaganda they were hearing. Again, not even close enough to overthrow the regime, but it had an impact on willingness to work and political affiliation.
What I'm saying is that, based on the results of the bombing campaigns in WWII,
social unrest to the point of giving up the war is out of the question. It wasn't going to happen. But there were negative effects beyond buildings actually being blown up. And I think those effects are abstracted into the "damage" done to infrastructure and factories.
Now, if strategic bombing could also hurt resource output, I'd be a happy man.
For reference.
Strategic Bombing Survey (Europe)
Strategic Bombing Survey (Japan)