Freedom of speech protects you from government persecution, not social stigma.
If you think that's okay because of the views this engineer holds, you're a terrible human being.
For example, libel, slander, and harassment may all take the form of "speech" but are unquestionably firing offenses. Those are also criminal offenses because the balance of harms swings away from the person who's free speech rights might be violated, toward the person who's own rights are being violated due to the exercise of free speech itself.
As that old adage goes: My right to swing my fist ends where your nose begins.
More likely than the lawyers saying the firing was legal, is that Google decided the cost of an illegal firing was less than the cost of keeping him onboard.
I guess you don't work in the United States? Because it's certainly fine for him to be fired for this.
Freedom of speech is the right to articulate one's opinions and ideas without fear of government retaliation or censorship, or societal sanction
Not just from government censorship, but from SOCIETY censorship as well
Governments, at least Western Government, are a reflection of society in general often delayed by a generation or so. As such if society deems fit to Censor something often that translates into the government censoring the same thing just a few year later.
We must be always mindful of threats to free speech not just from government but from society at large.
It is incumbent upon everyone to respect everyone else's freedom of expression, individually
It sounds like a facile reading of Mills, without ever going to the back half where he talks about valid reasons for a society to put pressure on an individual, but I've been more on the Federalist papers this year for obvious reasons.
The US Constitution is a document that outlines what powers the people of the US have granted to the Federal government, it has no bearing on what I am talking about
But the idea is bigger than the constitution. I think it is best expressed in The Friends of Voltaire: "I disapprove of what you say, but I will defend to the death your right to say it".
This is a deep idea. I think it is virtuous.
Silence no ideas.
freedom of speech is a far more general moral principle and social norm. we ought not conflate the two and there is much more utility in discussing the more general case of freedom of speech and not the narrower more legalistic case of the 1st amendment.