Congratulations, you totally missed the point of the original speech.
I don't think I did, and I sincerely believe that trying to apply it to the Reddit situation at all is disrespectful to its meaning.
When the speaker said "First, they came for the socialists", they meant something very specific by "came for." The Nazis were rounding people up, putting them in camps, stealing their property, and killing them. As they go down the list of types of people that "they came for," there is no confusion about what was going on. Everyone knew that it was bad, but they were unmotivated to act to stop it because they hoped they would be spared if they kept their mouths shut. The only way it could have been stopped was through the collective actions of people who were not yet targets, but they did not act.
What is happening at Reddit is not remotely similar to what happened in Europe in the 1930s and 1940s. Not only are people not being harmed by those in power, they aren't even being silenced. I don't care if Reddit shuts down racist subreddits, but it's not because I'm not a racist. It's because there is nothing Reddit could ever possibly do that would harm me in any way. They have no power to make the world worse. They CAN, however, make it a little bit better by removing this particular platform for people to threaten, harass, and intimidate people because of their race, gender, sexual orientation, or body type.
In whose reckoning or opinion?
In REDDIT's opinion. It's their site. They make the rules. Because not all viewpoints are valid, they are within their rights to make their own determination about which viewpoints should be represented on their site.
I'm not advocating shutting down groups because of their viewpoints, I'm advocating shutting them down for their specific actions. Threatening someone isn't just speech, it is an action. Encouraging someone to commit suicide is an action. Promoting violence is an action.