I think it is certainly a very fine line to walk and people (including Google employees) will definitely see it in a lot of different ways. But, reading this as an outsider, the note appears to me to address the situation very directly and conveys a real sense of urgency (more so than I have ever seen from any of my employers, at least).

"many points raised in the memo ... are important topics."

So what? Other points were a violation of the CoC. Goodbye, good luck, see you around the campus!

At every company in the world. You aren't seriously expecting a company code of conduct to be applied fairly in some sort of scientifically measurable way? The code of conduct is there to protect against the worst types of behavior, and plenty of bad behavior will slip under the radar. So what? It's not meant to create some sort of utopian workplace. It's meant to create a better workplace for those who have historically been discriminated against. So far, it looks like it has come in handy at least once in a very public way.