Basically lets you use VS Code from a browser. Integrated terminal works, Git integration, and many extensions work too
Local VSCode attaches to a remote VSCode backend. So you see the remote file system, remote shells and remote extensions running in the local editor. This works for both remote hosts and containers and is cross platform; you can develop on a remote Linux host/container using your Windows desktop, for example. This is invaluable for developing inside containers with isolated tooling, for instance.
It isn't fragile; it just works and is so transparent that it's easy to get confused about where you're actually working.
Oh wait, glad I checked because ~800MB of that is just old versions of the server.
https://code.visualstudio.com/docs/remote/remote-overview
It really is quite nice, especially for things like containers, WSL, or headless development on something like a Raspberry Pi.
I don't remember how it works in detail, but if my memory serves me well, you develop the code locally, and it pushes it and builds it there, and runs it. At the end of the day, you use your Eclipse installation on the local system, but develop at the remote system transparently.
I've used it 5-6 years ago, but didn't use it recently since I didn't need it. However, it's a very mature system and doesn't limit what extensions or plugins you use. It's just an overlay.
I'm using Eclipse since its inception, and probably won't migrate away ever, but it's nice to see alternatives. Also, I'd never touch VSCode due to plethora of reasons, but these are my own reasons and this comment box is not the right place for them.
The nice thing is, Eclipse is extremely portable in terms of configuration and installation, so collaborative development is not a big hassle on the Eclipse side possibly.
Lastly, Eclipse has added "Compile to Container" target, so it's actually pretty usable for modern development in today's world.
For example, if IDE want to do smart things it may need to read all jar in your class path, are you going to download the entire class path from the remote then? Also, that's Java and things are easier, what if the artifact is not cross-platform and client runs on Windows with the remote side being Linux?
Don't worry I know you can't do that with just SSH and tmux or whatever.
If you're asking for your editor to run a browser window under its hood and chew up your battery for tooltips on mouse hover instead of inputting a short key macro on cursor, then I don't know what to tell you.