> People always believed in crazy anti-Jewish propaganda since, at least, the first crusade.
Absolutely they did. However, even at that time, it seems (if wikipedia is to be trusted) that the Jew's roles as bankers was part of the reason for the massacres:
"Many crusaders had to go into debt in order to purchase weaponry and equipment for the expedition; as Western Catholicism strictly forbade usury, many crusaders inevitably found themselves indebted to Jewish moneylenders. Having armed themselves by assuming the debt, the crusaders rationalized the killing of Jews as an extension of their Catholic mission"
https://en.wikipedia.org/wiki/Rhineland_massacres
You are absolutely right that antisemmitism didn't suddenly pop up in 1922, or even with the creation of the "Protocols" conspiracy. But prior to 1922, antisemitism probably wasn't worse in Germany than most other western countries.
But as we consider the inflation we are seeing today, try to imagine how it would be if the inflation is not 5-10% but 29500%, as it was at the peak in 1923. In other words, it would take 3.7 days for your paycheck to go to half value. When you got your salary, you had to run to the bakery and buy as much bread as you could. Old poeple and people on a fixed salary would lose everything in an instant.
Even in the present age, especially after 2008, conspiracy theories involving the banking sector is everywhere, and there are still whispers implicating a Jewish conspiracy, if you listen. Now imagine standing at a corner in Munich on a day where the factory didn't need your work, too afraid to go home to your abusive wife who would beat and scorn you for not bringing food to the hungry family.
Imagine some small man with a mustache telling a very convincing story that comletely rationalizes your troubles. He reminds you about the Goldmann banker up the street, and the Ruben gem store at the corner. Their families are not hungry, yet they didnt "work" (meaning physically) a single day of their lives, they are simply collecting usury. Imagine being told this, while hungry, while worried about being beaten by your wife when you come home, in a world where anti-semmitism is still seen as acceptable, in a world where usury is still seen as a sin, in a country where the interest rates on loans have 5 digits.
What I'm saying is that those germans were just like us, just under different circumstances. To them, the jews were the socially accepted "bad guys", just as nazis and facists, and where people can label people as nazi or facist with not much more evidence than not liking that person.
The person that would say today, that "It's ok to punch a nazi." (meaning MAGA-republican), might very will be the person in 1923 thinking that "It's ok to punch a jew.". The reasoning is very similar. And it's not restricted to the left. People on the right are currently generating massive amounts of resentment against "the elites". And in some cases, the anti-semmitism is once again coming out into the open.