That's a charitable way to describe him. In our one direct interaction, he was condescending to the point of insult. (I believe he was incorrect as well, but even if he was always correct, I would consider it wrong to treat someone badly.) After browsing the Nim forum and issue tracker, I found that this was routine behavior for him.
Nim has some nice features, but I don't want to depend on anything that's subject to the whims of a personality like that, and I certainly don't want to interact with him again.