Ranges from language to language.

For example, VS Code pulls TypeScript definitions of your JavaScript dependencies and thus has superior intellisense.

Also, the plugin ecosystem uses JavaScript, so it tends to be more cutting edge, especially if you're working on a JavaScript project (i.e. same language as plugins). For example, VS Code and Atom had Prettier code-formatting when IDEA didn't. And they sometimes have the best support for newer languages like Elm.

I'd be wary of painting people as junior developers just because they don't use your preferred IDE.