I was going to reply that maybe they wanted a light application to develop for Arduino, but...

"The new IDE is based on the Eclipse Theia framework, which is an open source project based on the same architecture as VS Code (language server protocol, extensions, debugger). The front-end is written in TypeScript, while most of the backend is written in Golang."

A VS Code plugin might have been better indeed.

A VSCode plugin doesn't mean being lighter, the Java tooling from Red-Hat/Microsoft basically runs Eclipse headless, at which point I rather keep using Eclipse anyway.

[PlatformIO](https://platformio.org) has taken care of that so thoroughly for them, maybe they only think their IDE is worthwhile for people who don't want to use VS Code?

I struggle with VSCode because of the visual clutter. I know that I can set it up to my preferences, but haven't figured out how to make all the extra stuff go away. Also, IDE's seem to have an insatiable appetite for "improving" the UI elements rather than using standard elements from each platform, like scroll bars. I still can't use the scroll bars in VSCode or Spyder on a touch screen.

But with that said, PlatformIO is super impressive.

This tracks. I recall being surprised by the behavior of the Cmd+W keyboard shortcut in the new IDE that closed the window rather than the tab[1]. Keeping it simple seemed to be the main factor driving the way UX choices were made.

[1]: https://github.com/arduino/arduino-ide/issues/275

This is used extensively in classrooms. Providing this standalone editor that "just works" is more appealing in such scenarios than asking students to use vscode with extensions

Is there any limitation with VS Code extensions that could have prevented the effort?

pretty sure not