It's obvious from her words in the article. She wanted to bring people on board and the "old timers" didn't agree with her choices. Since the old timers are the epitome of a company's culture, then that means she was poisoning it. The options were to let her do it or let her go.

That's a poor conclusion. Saying that she was poisoning the culture is inherently making a judgement that the existing culture should be sacrosanct and that any changes are bad. This is poor reasoning. There is such a thing as bad culture. We don't have details on why there wasn't a "cultural fit," so its hard to say for certain, but if the culture was preventing successful execution of a project that the company was invested in, then I would say that the culture should be adjusted. And certainly, the way she described her interactions would indicate that the people of importance at Valve -- the hidden middle managers -- had a close-minded approach to working with people who's experiences did not match their own, if the story is taken at face value.

For what it's worth, I agree. But in this instance, Valve is the last bastion of hope for game programmers in the industry to work somewhere whose owners don't try to exploit us as money fountains. If there's a place whose culture is worth preserving, it's Valve's, even at the cost of this particular project.

Assuming its the case that you have to make a choice between the existing culture and this project, and that there is no compromise, that would be a fair justification. I have no idea if this is actually the case or not, since I'm not in the industry, so I'll just say that I don't disagree with what you said.

I don't understand -- when you hire someone most of the team isn't comfortable with, then you're making a compromise. And compromising on people is one of the worst mistakes a technology company can make, right? So why do you disagree?

Gonna Godwin this one a little:

What if most of the team isn't comfortable with the new hire because they're a woman, or they're black, or they're queer? Is it still implicitly a mistake to 'compromise' on keeping the team comfortable and protecting your culture? This isn't hypothetical, we've had recent examples (Kixeye, Stardock's Wardell, etc).

You simply have no evidence to support a claim that she was the problem. I think it's a bit ridiculous to jump to the conclusion that she was, given the things we all know about the game industry. Lots of other explanations are quite plausible in this scenario.

I said I don't disagree given the assumptions stated.

I do disagree with the unqualified assertion that "compromising on people is one of the worst mistakes a technology company can make." Culture is a broad term that covers a lot of things. There are important and unimportant aspects. If you reject a person because they can't work productively in your org, that's one thing. If you reject them because they'd rather go home to their family rather than participate in your after-work Starcraft sessions, that's another. Both can be considered culture, but only one is actually important to the working environment. Furthermore, marking it as the "worst mistake" makes the assumption that compromising on culture is necessarily destructive, which its not. Again, it really depends on which points you're compromising on.