It's a great strength that NeoVim supports many languages, and VS Code uses Javascript.
Lisp is not widely used, and this is an impediment to Emacs' popularity.
However, when people speak about Emacs customizability, they are referring to a deeper level of customizability than most programs (even NeoVim/VS Code), in which its innards and UI are all subject to modification, at runtime, within the beast itself. This isn't necessarily a good thing, but it happens to be my preference at least.