We can go on bandying what ifs forever, and all to little point. My contention is that the Allied Bombing Offensive by day and by night disrupted Germany's ability to conduct the war even more aggressively, particularly in the forced withdrawal to the Reich of Luftwaffe capability that could have been hampering, preventing maybe, advancing land forces on the major fronts that were converging on the Reich. Yes, day fighters of course, but the immense numbers of flak batteries and their crews as well. The latter as previously pointed out were there to deal mainly with the night bombing. The effect of releasing them to the Eastern Front (in particular the 88s) could have been devastating against the T34s of the Red Army. The Night Bombing Campaign was in effect the second front that Stalin demanded long before D-Day. It was his forces that progressively drove the Wehrmacht back from whence it came.
Civilian Morale if anything hardened as a result of city bombing. Even if it hadn't the population had little opportunity to do anything other than do as it was told and keep its mouths shut, agreed. But the night bombing had a great effect on production and man power resources. Even if it hadn't the chaos it created diverted even more resources to dealing with each and every raid. If the effort had moved away from the Reich then resources could have been switched elsewhere and in particular to the Russian front. We had no quibble about laying waste to German cities, then at least, but taking out targets in occupied cities was another thing entirely. They would have to be bombed by day, they would be better defended if this was now where the threat was. The success against such targets during BC's actual campaign was because the Luftwaffe was in the main defending the Reich. I repeat, the main effect of the Allied Bombing Offensive was to cede air superiority outside of the Reich. That led to Kursk, Italy, and Normandy, and the driving back of the Wehrmacht in those theatres