I think there's a problem with their data or their analysis. Vim is probably very well known and held with affection for a lot of developers whereas IDEs are far more subjective and occasionally hated.

There's also a fundamental problem of expectations. Vim is miraculous as far as terminal-based text editors are concerned. You can be amazing productive without a mouse. I can do 100X more and do it all faster with IntelliJ Ultimate but since I paid a wad for it, all I can see are the flaws.