I disagree with this for a few reasons. Having an editor or tools which feel cumbersome and don't get out of the way, in my anecdotal experience, may cause me to avoid it more often (visit sites like this for instance) etc.
In addition, often when learning new features of an editor or IDE, I enjoy applying it to actual code, which causes me to spend more time coding, which does impact SLOC.
Learning vim features such as autocomplete also save context switches where as previously I would have had to have a browser window open with the documentation. Just my two cents, I think it really does matter.
I don't believe he is saying to use any editor. We could easily list ten of the best ones than meet your standards above. Someone proficient in one of those is probably going to do just fine.
In addition, often when learning new features of an editor or IDE, I enjoy applying it to actual code, which causes me to spend more time coding, which does impact SLOC.
Learning vim features such as autocomplete also save context switches where as previously I would have had to have a browser window open with the documentation. Just my two cents, I think it really does matter.