With all due respect, I think you are simply overwhelmed. Specifically, this:
>which will have rippling negative effects around the world.
We don't know that.
>to what will very clearly be an abominable and destructive regime.
Nothing clear about that.
>I came today expecting a community making plans to protect the vulnerable, to save the planet from climate catastrophe, to ensure the economic environment that has allowed Silicon Valley to flourish. Instead: "I’m a huge fan of Zelda, The Wind Waker’s graphics.".
Silicon Valley was not born to protect the vulnerable or save the planet, but to create technology. Often in the form of games and graphics.
To calm your spirits, let me try to put it succinctly:
People are trying to infer what kind of president he will be based on what kind of candidate he was. This doesn't work. When someone is a candidate, their job is to win at the game of being a candidate. This involves a certain tool-set: Scandals, digging up skeletons, making dead people vote, disinformation campaigns, promising a utopia, coming out as crazy, whatever gets the votes. Some are morally higher than this. It might work, but I don't think they ever become presidents, especially when others are playing by certain rules.
When a candidate is elected, though, they are the president and their job isn't to be a candidate anymore, it's to be a president. It's different.
Candidate Trump was something, but President-elect Trump is another thing, POTUS Trump will be something else because he needs to be.