I'll try to rephrase my first two questions to address your semantic concerns:
1. When has a silencing action similar to the banning of /r/The_Donald been effective in reducing bigotry and/or fascism?
2. Your criticism of free speech is that it allows people to post subtly racist memes and dog whistles, but you haven't presented an alternative. How do you plan to deal with subtle racism and dog whistles?
I'm putting in an effort to use terminology that's amenable to you, so please put in an effort to understand my questions and answer them, rather than objecting to semantics.
> > 3. How do populations become and stay primed against open and earnest fascism/antisemitism/racism/etc....
> Education coupled with regular refreshers/responses as needed. If you want to teach kids anti-Nazism, it's not like you have to first invite an open and earnest Nazi to school to lecture the kids in class about how the Jews are subhuman and corrupt everything, etc. The anti-Nazi lesson can be taught directly.
Let's be clear: no one is proposing we bring earnest and open Nazis into schools. We're both on the same side: we both want to stop Nazis. So let's keep this on topic and avoid straw man arguments.
The anti-Nazi lesson can be taught directly, but in that teaching, you have to teach people the Nazi ideology, otherwise they don't know what they're actually against. And you need to keep that up-to-date, otherwise people are defended against what Nazis were saying 10 years ago. Nazism changes and adapts and we have to adapt to fight it. And if we're constantly paying attention to and responding to what Nazis are saying now, that starts to look suspiciously like just having an uncensored conversation.
If we don't do this, we run the risk of creating a generation of anti-fascists who can't recognize fascism if it doesn't have a swastika on it. This is already a problem: check out Dianne Feinstein, for example.