Or at least, there's a loud one, and I guess they figured it's also a big-enough one...
Say what you will about Electron apps in general, but Microsoft has done a great job in making VS Code not feel like a typical Electron app.
That's not really a fair comparison I think. JetBrains IDEs do a lot more than VS Code. You'd have to load it up with plugins to make something resembling a fair comparison, and in that case I'd be very interested in how efficient VS Code still is.
Fwiw before getting internet fiber, a 95MB file resulted in about 20 min download (my reference was 300MB an hour).
Electron apps are bloated ick but I guess at least Electron is equally repulsive on all OSes.
Out in real life no one knows or cares about this
My hope is that they create enough momentum to force the VSCode team to rewrite in React Native.