It's okay to express an opinion that is targeting a group of people (conservatives/Republicans/Trump supporters/etc.) if you belong to the right ideological group (progressives).
Don't think for an instance that this is the first case of controversial content posted internally. It happened all the time when I worked there, just that the group getting targeted wasn't in the majority in the social dominance and power hierarchy.
If I say something like that, I will (rightly) become a social pariah immediately and nobody would want to be around me.
Same thing with that guy. Yeah, you can joke about Trump, and you can joke about Hillary's emails, but saying that women are inferior due to biology makes you an unpleasant human being to be around and I don't want to be in the same room as you, much less on the same team or the same company as you.
If they hadn't fired his dumb ass, it would have sent a very bad message to all of Google's women employees.
There was more than just "joking." There was a hostile atmosphere for a lot of my peers who voted for Trump, akin to how women might have felt after this latest memo. The thing was, that it was perfectly "acceptable" (within the larger "Google culture") to create an environment hostile towards conservatives, with no Management backlash (probably because a lot of them felt the same way). The point was they didn't find that kind of "harassment" towards conservative employees problematic at all.
Computer programmers often make the mistake of treating other humans like cold, calculating machines. But they're not. They have emotions. Emotions, and past experiences, and history. And, unless you're in the extreme Asperger's spectrum of being unable to deal with other human beings, you should know, by age 15 or so, that there are certain subjects that are sensitive and that a company environment is not the place for them.
To help other potential programmers from destroying their careers, I'll post a short list of risky topics here:
* Politics * Race * The Holocaust * Sex
Any one of those could land you in hot water for creating a hostile work environment.
Nobody cares if you have scientific evidence that Jews make for inferior doctors, you don't post a memo claiming that in the company you work at. You just don't. Because you're working with other humans, not with machines, and you have to be smart enough to know what's acceptable office talk and what's acceptable poker night talk.
This Google Engineer is an idiot. I don't care whether he can "out-prgoram" me and code a complete OS in 2 hours. He's still an idiot. And deserves to be fired, because Google doesn't want to employ idiots.