You're right, they can only try. They can express concerns, they can interpret goals a little differently to minimize harm, they can stretch the truth and make the project seem less feasible. None of that is going to do much if management is driving this through - loudly resigning in protest is the last move, and unless you have a big name it's not going to do much.
But you're wrong that I'm coming at this as a consumer - I'm a dev and I've been put in this situation before (although our work wasn't public).
You're also wrong on the googler front - most of them aren't making that much, better than they'd make most other places, but not life changing amounts
When you talk to a googler, there's a pride, and buried under that usually an insecurity. They got into the bleeding edge of tech... Or so they thought.
Last Thanksgiving I was talking to someone who worked for them, and once the conversation got technical I could see it in his eyes. I happened to be well versed in the topic, and so I started asking questions about his approach. And as much as I tried to hide it (he is family) he must've seen the disappointment on my face... He just deflated. He knew deep down what he was doing wasn't actually that cool or special - it's just a lie that he hears constantly
Working at a company like Google, you're constantly being told you're doing important work that could change the world. There's pride and status there. They've crafted a bubble where everyone reinforces that belief, that "what we're doing is good and important"
When you step outside that bubble and realize the technical community doesn't respect you, personally, not because of Google but because of your own actions? That pokes a person right in the place they put their self-worth