I think it's just built up over time. I've never met Zed. I don't quite understand how he's built such a following -- it's quite possible it's because he's a nice guy who helps people. It strikes me from what I've read by him and about him that this SEEMS unlikely, but again, I do not know him.
The opinion that drove my response was that this was a monstrous waste of resources for github. Zed has influence and his blog post provoked a reaction that was unnecessary. We don't know how widespread this problem is on github. This is the first time I, or anybody I've spoken with, has even heard of anyone having this problem. Running a startup (I imagine), especially one with as much success as github, is almost certainly incredibly difficult. Reading a blog post rant by someone with influence has got to be a real bitch. And they handled it with grace and patience. Which is more than I can say about myself and Zed.