I dislike Electron as much as the next person, but I think a big part of the issue is that there really aren't great cross-platform options out there and it's hard to keep a consistent UX across platforms if you're reimplementing things for each OS.

I guess I'd ask: what would you (or other people here) use? There really isn't one that offers a great native experience cross-platform.

Flutter won't ship Chromium, but it'll bring along its own runtime, widgets, and rendering engine rather than using what's provided by the OS. .NET MAUI uses native widgets, but it's difficult to create one API that uses native widgets on different operating systems given that there are subtle differences between similar widgets on different operating systems. MAUI Blazor Hybrid solves that issue and doesn't ship Chromium, but you aren't getting native widgets.

I think for an editor to be successful, it needs to be available on Mac, Windows, and Linux and it's really hard to maintain parity if you're developing the UX separately. As I said, I'm not an Electron fan, but it does allow for easy parity across platforms.

In this case, the reason it's Electron is that it's not just meant to challenge VS Code, but it's essentially the same codebase as VS Code - like how Edge is the same code base as Chrome. The point of the project was a VS Code that was truly free software rather than an open source core with a bunch of Microsoft stuff around it.