Google engineer who protested company's work with CBP says she's been fired

This was never a reasonable thing to use as a code of conduct. Ironically, it only works if you restrict your hiring so that everybody that works there has the same point of view or same values. As hard as it is for many people to believe, almost nobody actually thinks they are "evil" or even what they are doing is "evil". On the contrary, the Dunning-Kruger effect will rear it's head. Those that are most likely to do "evil" are also the most likely not to recognise that it is "evil" and, in fact, will think it is the correct thing to do.

Just take any political stance that you think is evil. There are thousands and probably millions of people who think it is not only a good idea, but possibly the only good idea. If you don't do it, you are ruining everything and only "stupid" people can't see it. I could go very extreme here and point to real work examples, but in an attempt to avoid Godwin's law, I'll try to refrain. To be very blunt, though, pretty much all hate speech includes rhetoric about how they are combating "evil". By encouraging all people to speak out against what they see as "evil", you are likely encouraging the opposite of what you are trying to achieve (unless your goals are chaotic shouting matches between hordes of people who all hate each other).

Dont really see how that applies here. Whether or not you support open-borders is really just asking if you support the abolition of worker rights and cultural genocide. Google is clearly on the right here.

most software engineers are paid well. but they still have moral consideration. this does feel like retaliation.

They are paid well, but Google (and other companies) have discovered that their workers are most productive not when they are mercenaries, but when they are "part of the family". Thus Google (and other companies) try to create an environment where if workers don't like something, they are encouraged to help steer the boat. Of course when this conflicts with actual business interests, everyone sees who is really holding the wheel. This can be jarring for workers so used to feeling "part of the team".

This "they're paid well, so they should do their job or leave" idea misunderstands the culture these companies work to uphold. If Google wanted to hire mercs they certainly could, but in the past their values were the opposite of this. In the future, we'll see.

Your position is that if your employer pays you a sufficient amount of money, you mustn't ever consider anything your employer does to be unethical to the point of pushing for them to stop doing it?