Most Germans didn't know about the atrocities until after the war. If Germany closed down the media so well, the people might not have known about mass suicides either.
The only way that loosing the support of the uninformed German masses would have stopped the Nazis is if those previously uninformed German masses took up arms against their government. The Nazis were only going to stop killing once there was nobody left to kill, or once they were killed. They played by a different set of rules.
And they needed active support from the "uninformed German masses" - why do you think Goebbels was their 3rd or 4th most important man? The support was gained through propaganda, and the core parts of that were the all-around (including moral) superiority of the Aryan race and in contrast the portrayal of Jews as its absolute enemy, both despicable and threatening.
If that propaganda had been revealed as a lie via large-scale non-violent protests, it would have caused serious and quite possibly unsurmountable problems for the Nazi government - they did not have nearly enough hardened ideologues to run the entire country.
No, I don't think that.
What I think is that are a fine example of people who could not be stopped with anything but violence. Killing or letting them have their way were the only options.
They likely could not have run the country without the support of the German people (I'd like to point out that it is not clear that they could have run the country _even with_ the support of the German people; they were still on a self-destructive trajectory even if they had not been at war with the Allied forces...) but they could have kept the slaughter going. While having an industrialized society does make genocide more efficient, it is by no means a prerequisite for genocide.
The Nazis required propaganda not because they were afraid of what would happen if the German public became peacefully non-cooperative. They needed propaganda to 1) prevent a violent rebellion in Germany and 2) remain strong in the face of violent opposition from the Allied forces.
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Succinctly put:
I do not believe that the Germans were pure monolithic ultimate evil.
I do not believe that this would have been a winning strategy:
"You will invite Herr Hitler and Signor Mussolini to take what they want of the countries you call your possessions. Let them take possession of your beautiful island, with your many beautiful buildings. You will give all these, but neither your souls, nor your minds. If these gentlemen choose to occupy your homes, you will vacate them. If they do not give you free passage out, you will allow yourself, man, woman and child, to be slaughtered, but you will refuse to owe allegiance to them."
Against the Nazis, I believe that is the strategy of a fool.
What is clear is that the German people knew something was afoot. Perhaps they did not know that there were camps build for the express purpose of extermination, but the sure as hell knew there were mass deportations, families being disappeared, and concentration camps (a concept that is distinct from death/extermination camps).
However, when I talked to those granddads, it became very clear that they knew what was going on. They not only had a sharp memory of what happened, but also tried to make their ideology and actions appear harmless. It's always the same story. "I had no idea what was going on. And what could I have done, even if I knew it?"
The stinky story falls apart, when they start explaining how it was back then. After an hour of talk you get the sense that they try to defend something that is simply illogical. Most Germans today, don't agree with any part of the NS-Period, but cannot get rid of their own hate against Jews, colored people or different people. You've recently read this story about the guy who got him self arrested, right? Try to suit up like a Jew, a Black, a Gay or any other enemy of the old regime and you will really understand how it is. On Halloween you can go out as one without looking weird, but even though the setup is artificial, I'm sure you will get reactions that you wouldn't expect and from people from whom you wouldn't expect it.
Once a disabled man knocked our door and asked for a signature. He tried to use sales tactics to get his signature, but when I found out what it was for, which he strongly tried to hide, I was shocked. He blatantly tried to get our votes for their nazi party. That's not a year ago. Of course, I told him to go the f* out of here and that he should read a book, which explains how his own party burned people like him alive, and then think about his political views.