Here they fired him not for perf (defensible) but for difference in opinion (maybe defensible but icky) not anything bad he did. I think he stands a better chance than Pao's retaliatory suit.
He wrote the manifesto and distributed it within the workplace. That's absolutely an action he took at work, that's a thing he did.
See also the Shoe Rebellion: https://news.ycombinator.com/item?id=12022280
You don't have freedom of speech at work. Apparently in the US that's not a freedom of speech issue until the Government says you can't say certain things at work.
Pao's issue was shown to be a non-issue, yet "it brought the issue to light" ok...
I wonder why the author didn't mention the resolution of the lawsuit? I wonder why she mentioned it all? Oh right, peddling falsehoods, both explicitly and implicitly.
People in general can sue anyone if there's any possibility they might win. The only way her lawsuit would be thrown out if she had never worked for them, or something like that. Otherwise, the way to find out if her claims have merit is the lawsuit.
Which she lost, and was forced to pay $276k to KPC&B. So not exactly a good omen.