No matter how you read the original manifesto or the responses to it, I think there's a level of separation one must achieve before they pass judgement on it. If you let yourself live in the binary black-and-white world that the manifesto author created, where views are either left _or_ right, you're bound to get fired up. This is a natural reaction to the fact that party identification and attacking identity tend to trigger much more primal responses than if party was removed. In my humble opinion, Google is a very good example of a company with a mixed culture. They're a hugely conservative company in how they manage their finances, pay taxes, hire employees, and operate their company to the normal world. At the same time, they attempt to create "Googley" spaces where thinking and diversity are promoted. Are these necessarily right wing and left wing ideologies? Maybe. But it's definitely a mix -- you don't see Google spending 100% of its money on social programs, nor do you see it spending 0% of its money on social programs.
Does the manifesto author have a reason to write? Yes. He's clearly scared, and clearly feels attacked, perhaps on a regular basis, in the workplace. Like many an engineer before him, he attempted to identify the problem and presented several solutions that may or may not work.
Now, were the solutions he presented the correct ones? I personally am inclined to say no. Just as Carl Sagan said, extraordinary claims require extraordinary evidence. The article was eloquent and well pointed at specific "problem areas" the author presumed to be at fault. The author did not provide anything to corroborate his hypothesis that things like removal of empathy would do any good to help the situation at Google. Similarly, the author's attack on outreach programs aimed at minorities did not make any effort to show how these programs were exclusively harming non-minority participants.
Now, obviously, there are questions on the other side of the plane too -- specifically on whether or not diversity initiatives help or whether or not empathy helps either. I haven't done this research -- but the author hasn't done his research, so I feel this is fair. I'm just pointing out that Google is a for-profit company. They tend to make decisions that are economically viable, and they may or may not have done research on these types of things in the past -- though I would assume they have. Again, this is a company infamous for A/B testing shades of blue for engagement. It would be silly if they were burning their cash pile on programs known to be detrimental or non-working.
To summarize: if you write a manifesto, I expect you to pull some figures and prove some points before you start pulling the political party card and getting everyone riled up about your thoughts and opinions. If you read a manifesto, don't conflate perceptions as fact without examining and thinking about them closely for a long period of time. It will ONLY lead to pointless arguing and senseless fighting, while the real issue gets ignored.