It's very featureful and very easy to pick up. So I speculate that most of its popularity is with people that unfortunately have not yet been enlightened by vim/emacs.
The article said 1.4 million people have installed the Vim plugin for VSCode. That's a sizeable chunk. Presumably a bunch of those people really like the editor.
I used Vim for several years before switching to Sublime Text 3.0 and now VS Code. VS Code support for TypeScript is just unmatched on any other editor.
