If you read Holocaust survivors memoirs you will learn many things.
During Operation Reinhard the killing centers were unthinkable and also veiled under strict secrecy. The information was so unbelievable that although there was early intelligence out of Chelmno for gassing vans, and later Slovak escapees published a document detailing the operation of Auschwitz-Birkenau II, it was met with disbelief and treated similar to a conspiracy theory. Wartime propaganda made this worse, by spreading so many rumors that people could not know what to believe.
The killing process was so barbaric that even prisoners who had witnessed it while doing other tasks in the camps, were in denial about it, as per their own memoirs. When Rogerie, member of French Resistance / primary witness against Holocaust Deniers, arrived in Auschwitz the first thing the French doctor told him was that the gassings were taking place, and he did not believe it until he saw with his own eyes. Even today are pretty foggy about what exactly happened in and around gas chambers.
The Nazi deception and subterfuge apparatus was so ubiquitous that in lots of cases people thought they were going to take showers. The killing centers were idyllic in appearance, and were made to the last detail to look like innocuous intermediary stops. Nobody escaped these places with the sole exception of the Sobibor uprising, and the Slovak Birkenau escapees. Churchill only came to know about the gassings around the time of the Nazi negotiations with Hungary about deporting Hungarian Jews to Birkenau, which was later in the war. The Sonderkommando photographs were taken during the cremation of the bodies of Hungarian Jews. Those three sources were the only hard evidence about the gassings up to late 1943, I think. It was a very well protected wartime state secret.
This is not to say that there were no rumors about it, nor that it wasn’t common knowledge among certain segments of the German population. But, for many Jewish people what we now know was a wild conspiracy theory they thought too stupid to believe. They also had some more everyday shit to worry about. They were facing boycotts, pogroms, malnutrition, and were deported into ghettos and camps. Some were better off, for example in villages, and they didn’t want to live as refugees in Ukraine.
Nazis had installed Jewish Councils to take care of such villages, and these councils were selecting people for camps, believing it would be just very hard labor. Wealthier families could pay the councils off to evade recruitment. When Operation Reinhard started the villages were surrounded by Trawniki men in the early hours and they would round up as many Jewish people as they could fit in the trucks. At this point people would start hiding in attics and special hideouts in the homes, while the Nazis started moving vast numbers of people from ghettos into Jewish villages, where they would be soon taken by the Trawniki’s to the killing centers.
At this point it would be almost impossible to escape the villages alive. Some survivors report they tried, but not succeed. But people did not have sufficient and/or reliable information to act on before it was too late. Jews from other European countries, like Dutch, Greek, etc, they would ride a train from their hometown and end up in a gas chamber in a matter of days. Most of the victims from outside Poland would have had a few short minutes available to realize what had happened to them.
In fact, nobody talks much about this period apart from survivors. They all express the same concern: Don’t let this be forgotten. It can happen anywhere, and it will definitely happen again, if not by the exact same means, by equally barbaric ones. If you read the whole thing from the 1930s prison camps up to Operation Reinhard killing centers you can have a rough idea about how they will go about it.
Probably they will build the deportation camps for illegal immigrants, make gender non-conformity a sex crime, get trans people in the prison labor system, then upgrade many prison to work camps. At the same time by prohibiting transition and denying healthcare they will decimate trans people by suicide or malpractice, and when they have the opportunity, for instance: during time of war, they might as well build gas chambers because deportees are too many to humanely deport, and put trans people and leftists there as well. I mean, they have followed the Nazi playbook to the letter so far, why would they stop now?
Sounds crazy, right? It sounded as much crazy in 1942, but it is true.
Actually the “International Jewry” bullshit is very much like the “WOKEism/Gender Ideology/DEI” shit we see today: If you replace “Aryan” with “White/American” as well, it is pretty much the exact same thing. This started gradually taking over the state apparatus, with many Germans jumping on the train around 1936. By that point people would be sarcastic and cynical towards the attempts of the state to be more “Aryan”, but at the same time the Jews were construed as alien and curious, and Germans would stop meeting them, so they were made into an out-group first, then vilified.
A good source on this that does not focus on the Holocaust per se is A Social History of the Third Reich.
If you consider that the “Hitler’s prophecy” was uttered in 1939 and several more times after that, but it didn’t even make front pages, then yes. But keep in mind not all historians agree on that. Some say that the “vernichten/ausrotten” (exterminate/kill) rhetoric was ubiquitous in Hitler’s, Himmler’s, and Goebels’ speeches, and that German people knew where this was going. I am not decided yet, and I want to believe the first, but I have read strong arguments about the Nazis having been explicit in their genocidal plans from the very start. (eg Jeffrey Herf “The Jewish War”)
Not everyone can emigrate. Some people are too poor to emigrate. Even then, and I keep on the Holocaust story, the Saint Lewis incident shows that people were not welcome to emigrate (in the US, which is no coincidence), and they were sent back! In the US some people think that the federalist situation will allow states (California etc) to keep doing their thing, but the fascists now have the federal government, and the militias. So we don’t know for how long the progressive states will continue be free. Then if you speak for actually emigrating abroad, that would be even more difficult for quite a lot of people.