German here. Given what they fought against, yes it was. Visit any of the too many concentration camp sites across Europe... it's definitely worth the time.
The deliberate terror bombings that constituted some part of the effort, especially in the mid and late years, were also and separately awful, though the ethics somewhat muddied by the targeting of civilians having undergone a tit-for-tat ratcheting up early in the war, and yeah, the whole death camps thing. But there too the question of whether those deaths served any useful purpose, as far as ending the war sooner or reducing its scope, makes the whole thing even sadder.
Well, given that an utter majority were supportive of the Nazi regime up until and even after the war ended... I'd say it was necessary, if only to set an example for any future offender just how brutal the crackdown will be.
Unfortunately, the world failed to keep the reminder up on "genocide = bad and WILL lead to a brutal response" - the response towards Serbia in the 90s, Russia after 2014 or Syria was way too lackluster IMHO.
The daylight raid aspect, however, seems to me to be more grounded in ego and dogma than military utility. I don’t think avoidance of civilian casualties was a deciding factor. Those airmen were sent into a meat-grinder.
They were, but also remember that back in 1945 there was no such thing as GPS or any kind of more precise navigation than a compass, a sextant and star charts. It was very easy to get lost at night or to hit some mountain, particularly as Germans were pretty strict in enforcing Verdunkelung [1].
Flying during daytime was obviously more risky because AA defense can see you, but it was also less risky because navigation was easier - and more precise, because you could actually see where you were.
Mass murder of civilians isn't morally acceptable no matter what the "other side" is doing.
Firebombing a kindergarten in the Rheinland doesn't do anything to help someone in an extermination camp in occupied Poland.
Post war analysis of allied strategic bombing indicates that it did not have a large impact on the war effort and probably wasn't worth the high rate of loss of the expensive airframes and crews.
The bombing didn't cause the German people to overthrow their government like Allied leaders hoped it would, but it did significantly impact the war IMHO by decreasing German production of essential materials like refined oil products, particularly lubricants, ball bearings, airframes and probably other materials.
Even if no factories had been hit, just the fact that the Germans underwent the expense and inefficiencies of distributing manufacturing among many small factories, some underground and some in caves (which the Germans did in fact do) would still have significantly decreased German production.
It can make evaluating things like this tricky. So a raid that lost dozens of bombers and cost weeks in training time only put some part of their industry out of action for a couple weeks and diverted a week or so of other factory productivity for the rebuild and retooling effort—that looks bad, but could still actually be a deal you should take every time under certain circumstances.