1. I applaud the fact that they are actually quitting the company to voice their disapproval of these policies. In my mind all the "internal activism" happening at Google and others is massively hypocritical. One cannot publicly criticize a company while enjoying cushy paychecks fueled by those very activities they despise.
2. If they think Google is discriminatory towards LGBT employees and minorities, contributing to climate change etc., they are in for a big shock once they are really out of the Google and SV bubble.
Why is it that you think that the people who see the sausage being made are exactly the ones most unqualified to criticize it?
And in a few cases, yeah; HR is shitting bricks because it's losing people who built the underlying fabric of the system (which anyone who has built a large system will tell you increases risk to the entire software company; they're pretty sure the exiting employee has written down all the mission-critical knowledge of how to operate the system riding around in their head, and Google has a corporate culture of minimizing the "bus factor" of key systems, but there's always a risk that the next time something significant catches fire, the employee with 1.5 decades of experience who just walked out the door is the one who could have fixed it fastest).
It'll be interesting to see if quality of product suffers (i.e. if there was actually correlation between technical competence and a care about the fate of the world and fellow employees).
And apparently that mindset drove an enormous amount of profit and, at least in the beginning, gave the company some sort of social conscience.
It's amazing that you can be so against these things