Microsoft has done a fine job with VS Code considering it is built on Electron, but it's a freaking text editor ffs! It has basically zero need for a UI. If this were 1990 and there were no cross-platform filesystem, i/o, network, async, etc. APIs available for native applications, it might make sense. But a text editor is basically the very simplest cross-platform UI you could ever need to design (proper text metrics and rendering is the only gotcha, but if you just shell out to freetype and DirectX rather than doing it all yourself, it's not really a problem).
VS Code is only fast because people compare it to the likes of Atom (which has thankfully dwindled in usage), GMail, and Slack. It doesn't hold a candle to the responsiveness of, say, basic native text editors like Notepad or Text Edit.app, or even horribly written "native" software like Notepad++ back in its heyday (although they might have cleaned up that mess in the decade and a half since I last used it -- I see Scintilla has switched to C++17!). Sublime Text was originally written by just one person and doesn't use a pre-packaged cross-platform editor widget, yet Skinner managed to do it without bundling in the kitchen sink and it shows.
Microsoft has realized this of course, and since the initial release VS Code has shied away from actually using Electron and many features are not implemented as HTML elements/nodes and instead are written bypassing the abstraction entirely because it's literally not possible to get the sort of responsiveness users (sometimes, incredibly meekly and never if they have to actually pay something for it) demand from a code editor if you have to go through Chrome/Chromium's abstractions to do it.